stratificationn.
/ˌstratᵻfᵻˈkeɪʃn/, U.S. /ˌstrædəfəˈkeɪʃən/ 1. † a. The laying down of substances in adjacent layers; esp. the placing of layers of a solid fuel such as coal alternately with a substance to be heated, as in calcination, cementation, firing, etc. Also: an instance of this; a series of such layers. Obsolete.
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the world > space > relative position > condition of being external > covering > a layer > [noun] > layered arrangement
stratification1617
stratifying1683
bedding1860
1617 J. Woodall Surgions Mate Termes 348 Stratification, or stratum superstratum well knowne to Chymists, and vsed in cementation, is strewing of corroding powder, or the like, vpon plates of mettall by course.
1665 R. Hooke Micrographia 47 When you have thus filled your Crucible, by continual stratifications of the filings and powder,..place the Crucible in a gradual fire.
1669 W. Rowland tr. J. Schroeder Compl. Chymical Dispensatory i. xiv. 21 Stratification [L. stratificationis vox] in Beguin comprehends the whole Art of Calcination, by which the Plates are made brittle, this they say is Cæmenting.
1704 J. Harris Lexicon Technicum I Stratification, or stratum super stratum, as the Chymists call it, is putting different Matters Bed upon Bed, or one layer upon another, in a Crucible in order to Calcine a Metal or Mineral.
1765 T. H. Croker et al. Compl. Dict. Arts & Sci. II. at Ferretto Make a number of stratifications of plates of copper and powdered vitriol alternately in a crucible.
1787 R. Watson Chem. Ess. V. 251 Copper combined with sulphur by stratification and cementation... Æs ustum.
1815 J. Smith Panorama Sci. & Art II. 302 Stratification, an operation in which bodies are placed alternately in layers, in order that they may act upon each other when heat is applied to them.
1882 Encycl. Brit. XIV. 385/1 It was formerly the practice in England..to tan by the process of stratification, for which purpose a bed of bark is made..; upon this is laid the hide, then bark, then a hide, and so on.
b. The placing of layers of seeds close together between layers of sand, compost, etc., in order to preserve them or (typically) to promote germination by exposing them to a moist, cold environment for a specific length of time.In later use also denoting the promotion of germination in this way without the seeds necessarily being placed in layers.
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1827 Franklin Jrnl. & Amer. Mechanics' Mag. Oct. 285 The stratification in dry sand, is a precaution which alone would preserve their germinating property for many years, and during the longest voyages.
1899 Bristol Mercury 3 Jan. 2/4 The time at which stratification must be commenced depends..upon the length of time the particular kind of seed to be treated takes to germinate.
1914 F. Moon & N. C. Brown Elements Forestry vi. 103 Commercial houses rarely practice stratification, because they have storehouses where moisture conditions are kept uniform.
1928 Jrnl. Forestry 26 775/2 Stratification of these seeds for one to four months previous to planting has been found to hasten greatly their germination.
1976 H. L. Edlin Nat. Hist. Trees xiv. 181 The seeds of ash trees..and many other common genera..require stratification for sixteen months.
2007 Univ. Oxf. Bot. Garden News No. 67. 4/2 Others that produce seed later in the season usually require a period of stratification to break dormancy.
2. Geology.
a. Each of the strata produced by successive deposition of layers of sediment; = stratum n. 2a.
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the world > the earth > structure of the earth > structural features > sedimentary formation > [noun] > stratum
coursec1430
couch1661
stratum1671
dess1673
strata1676
bed1684
floor1692
flooring1697
stratificationa1703
rock1712
liea1728
lay-bed1728
post1794
the world > the earth > structure of the earth > formation of features > sedimentation > [noun] > stratification
stratificationa1703
superposition1794
a1703 R. Hooke Disc. Earthquakes in Posthumous Wks. (1705) 348 Earth must be posited in certain Layers or Stratifications of divers kinds of Substances.
1781 Monthly Rev. 65 App. 551 He observed some singular stratifications, viz. some of ‘a circular form, leaning, as it were, with their convexity against the side of a mountain’.
1808 W. Richardson in Philos. Trans. (Royal Soc.) 98 220 Regular stratifications on the summits of hills and mountains, have been long a stumbling block to theorists.
1861 Rep. Select Comm. Income & Prop. Tax 249/2 in Parl. Papers (H.C. 503) VII. 1 Iron ore and coal are not found together, but in different stratifications.
1932 Bull. Nat. Res. Council (U.S.) No. 85. xiii. 451 The mud on the floor of the ocean is sharply stratified, and since its accumulation is very slow, these stratifications are the result of changes during a great length of time.
1967 M. J. Coe Ecol. Alpine Zone Mt. Kenya 76 The clays show a certain number of darker stratifications.
2010 A. P. Anzidei et al. in R. Runiciello & G. Giordano Colli Albani Volcano 347/1 The constant presence of sands in the earliest stratifications suggests in fact frequent overflows of the water courses, damaging the settlement.
b. The formation of natural strata by successive deposition of layers of matter, typically a sediment; the manner in which a sediment, rock, etc., is stratified.
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1795 J. Hutton Theory Earth (new ed.) II. ii. ix. 307 This summit is of solid granite, a mass in which there is no stratification.
1830 C. Lyell Princ. Geol. I. 203 The planes of stratification are perfectly parallel.
c1876 Pop. Educator (new ed.) III. 56/1 Abundant evidence is given to show that all rocks exhibiting stratification have been deposited by aqueous action.
1913 A. W. Grabau Princ. Stratigr. 697 Among the pyrogenic rocks stratification is produced where lava streams of different composition succeed each other.
1951 C. C. Gillispie Genesis & Geol. ii. 44 The Neptunist synthesis explained stratification by postulating that all rock formations had been precipitated from an aqueous solution and suspension.
2013 Jrnl. Geol. (Chicago) 121 543/2 Silicic magmas are expected to show stratification in silica contents within the crust.
3.
a. The existence or formation in a gas or mixture of gases (typically the atmosphere) of distinct layers which differ in physical parameters, esp. temperature, humidity, and pressure; an instance of this; (also) a single layer of this kind. In extended use also: the separation of cloud or smoke into layers.
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1810 Lett. & Papers Agric. (Bath & West of Eng. Soc.) XII. 356 A real though invisible stratification in the atmosphere of an air-tight room.
1842 J. Nasmyth in Pract. Mechanic & Engineer's Mag. 1 431/2 (heading) On the application of the law of definite proportions to the stratification of clouds.
1910 F. G. Benedict & T. M. Carpenter Respiration Calorimeters 27 To avoid temperature fluctuations due to possible local stratification of the air in the laboratory, the calorimeter is constructed so as to be practically suspended in the air.
1947 Proc. Royal Soc. A 188 218 The results of this section indicate that the drag of the earth may be obtained for any thermal stratification.
1992 R. McIlveen Fund. Weather & Climate 1. 3 Corresponding to this marked stratification of the structure of the atmosphere, there is an equally marked stratification of its behaviour.
2014 S. Hammersmith Cold Air Accumulation & Grower's Guide to Frost Protection iii. 17 Clouds and wind will destroy stratification, as will surface fog and overhanging trees.
b. Each of two or more distinct layers in a volume of liquid (typically a lake or other body of water) which differ in physical or chemical parameters, esp. temperature and density; the existence or formation of such layers. Cf. stratum n. 2c.
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the world > the earth > water > lake > [noun] > stratification according to temperature
stratification1860
epilimnion1910
hypolimnion1910
microstratification1931
metalimnion1935
mixolimnion1937
monimolimnion1937
1860 M. F. Maury Physical Geogr. Sea (ed. 8) xxii. 482 Let us, in imagination, divide these depths [of the sea]..into any number of stratifications or layers of equal thickness.
1898 Amer. Naturalist 32 26 It is in a condition of ‘inverse stratification’, as Forel calls it, when the colder water is above the warmer.
1935 P. S. Welch Limnol. iv. 51 Exceptional meteorological conditions may..prevent stratification completely.
1973 P. A. Colinvaux Introd. Ecol. xviii. 249 If a lake is highly productive, thermal stratification has some interesting consequences for the bottom water.
2009 Independent 3 Jan. 34/6 The proposal to pump up cold water from the ocean bottom to bury the surface waters and the CO2 in it, and in the same stroke of genius mucking up the temperature stratification.
4. The process or result of being formed or arranged into layers; the fact or state of having layers. Also figurative with reference to things conceived of as constituting a series of layers. Frequently in archaeological contexts (see stratum n. 2d).
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1826 Lancet 4 Nov. 150 It is well to observe, that in well made bread the vesicules produced by the disengagement of the gas, are regularly arranged in a sort of stratification of layers one above another.
1862 J. H. Burton Book-hunter (1863) 113 The library is the great intellectual stratification in which the literary investigator works.
1885 Amer. Jrnl. Archæol. 1 187 At about half the height of the mound slight indications of stratification are apparent here and there.
1910 Encycl. Brit. I. 248/2 By exact observation of stratification, eight more periods have been distinguished by the explorer of Cnossus.
1964 M. Mansoor Dead Sea Scrolls ix. 66 The stratification of archaeological context in which they are found must be taken into account.
2001 P. Mason Lives of Images v. 131 Beginning with composite images, we will unravel the stratification of their different source material.
5. Biology and Medicine. The thickening of a tissue by the deposition or growth of successive thin layers; the separation of a tissue into layers, or the deposition of a substance in layers. Also: the result of this; layered structure.
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the world > life > biology > substance > [noun] > layer(s) of tissue > thickening of tissue
stratification1830
1830 Amer. Jrnl. Med. Sci. 5 345 The mass was perfectly homogeneous..and nothing was apparent of that lamellar arrangement or stratification, so generally found in aneurismal sacs of the large class.
1875 tr. De Bary in Jrnl. Bot. Oct. 301 In Chara fragilis,..this membrane shows a copious tender stratification after the carbonate of lime has been dissolved.
1887 T. W. Shore Elem. Pract. Biol. Veg. 10 Observe..Stratification of the cuticle, i.e. the appearance of lines in it, parallel to the surface of the section.
1890 J. Cagney tr. R. von Jaksch Clin. Diagnosis iv. 65 In some diseases, as in abscess and gangrene of the lung, there is marked stratification of its [i.e. the sputum's] parts.
1922 Brit. Med. Jrnl. 21 Jan. 12/1 From miliary aneurysms they differed in their failure to show any trace of fibrinous stratification, any thickening of the wall, or anything but a suspicion of endarteritis.
1958 Internat. Rev. Cytol. 7 86 Apart from this orderly stratification, changes of a more anaplastic nature were observed.
1988 M. K. Dasgupta Princ. Plant Pathol. iii. 419 The classical concept..implies the stratification of the cell wall into lamellae composed of substances such as wax, cutin, cellulose, pectin, etc.
2015 J. S. Lim in W. H. Kim & J. H. Cheon Atlas Inflammatory Bowel Dis. viii. 136 (caption) Axial CT image shows mural thickening with stratification in the rectum and sigmoid colon.
6. The formation or establishment of social or cultural strata resulting from differences in occupation and political, ethnic, or economic influence. Cf. social stratification n. at social adj. and n. Compounds 2, stratum n. 3b.
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society > society and the community > social class > [noun] > division into classes
stratifying1683
stratification1844
social stratification1850
1844 Q. Rev. Oct. 286 From Thierry, we have learnt to appreciate the importance of investigating the internal stratification of society.
1879 S. Baring-Gould Germany I. 2 The stratification of the German classes, and of the aristocracy, is most peculiar.
1944 S. Putnam tr. E. da Cunha Rebellion in Backlands ii. 117 It was natural that the deep-lying layers of our ethnic stratification should have cast up so extraordinary an anticlinal as Antonio Conselheiro.
1973 P. F. Lazarsfeld Main Trends in Sociol. ii. 28 Legitimation and stratification in which the new middle groups, unable to free themselves from traditional symbols, simply aristocratized themselves.
2003 From Victoria to Viagra (Wellcome Trust) 11/1 He developed a model of ‘social darwinism’, arguing that the stratification of society simply reflected the way life operated.
7. The formation of luminous striations when an electrical discharge passes through a highly rarefied gas; the existence of such striations; each of the striations so formed. Now rare.
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the world > matter > physics > electromagnetic radiation > electricity > discharge of electricity > [noun] > container > striated appearance
stratification1853
stratum1856
1853 tr. J. A. Quet in Chemist 4 244/2 I obtained at the positive pole long columns of a beautiful white and phosphorescent light, whose stratification occurs in sensibly plane layers of unequal thickness.
1856 Proc. Royal Irish Acad. 1853–7 (1858) 6 429 When a Leyden jar (each coating about a foot) was connected with the terminals, the stratification was well seen in each direction of the current.
1858 Philos. Trans. (Royal Soc.) 148 1 The phenomenon of stratifications in the discharge in vacuo were subsequently observed in Paris by M. Ruhmkorff.
1902 Proc. Royal Soc. 69 399 Experiments on the stratifications exhibited by the purified gas under the influence of an induction current.
1996 P. S. Landa Nonlinear Oscillations & Waves in Dynamical Syst. xxi. 374 The standing striations, manifesting themselves in a spatial stratification of the plasma constant in time, are a special type of waves with zero frequency and non-zero wave numbers.
8. Variation or inhomogeneity in the richness of the fuel–air mixture in the cylinder of an internal combustion engine, esp. as designed to give greater control over ignition and combustion.
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society > occupation and work > equipment > machine > machines which impart power > engine > internal-combustion engine > [noun] > fuel or air mixture
stratified charge1886
compression1887
stratification1914
swirl1926
secondary air1931
squish1934
1914 Jrnl. Amer. Soc. Mech. Engineers 36 187/2 Stratification of the mixture and constant compression versus throttling of gas and air and variable compression.
1922 H. R. Ricardo Internal-combustion Engine I. v. 75 In order to increase the range of power as far as possible, every effort is made to encourage stratification.
1981 Sci. Amer. May 45/1 The stratification also makes it possible to burn fuel-air mixtures so lean in fuel that they would not burn if the fuel were uniformly mixed with the air.
2011 A. Weigand et al. in Internal Combustion Engines (Inst. Mech. Engineers) 113 The injection process offers a number of very effective variables to positively affect the stratification and mixture formation in the combustion chamber.
9. Statistics. The division of a heterogeneous population into non-overlapping homogeneous groups so that each may be sampled independently and these samples combined to form one of the entire population.
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the world > relative properties > number > probability or statistics > [noun] > groups or arrangements of data > division or arrangement into
stratification1920
rotation1935
ordination1954
1920 A. L. Bowley Elements Statistics (ed. 4) II. iv. 336 The stratification of a universe of measurable objects is also treated by Mr. Yule.
1966 Rep. Comm. Inq. (Univ. of Oxf.) II. 420 In drawing the sample stratification by college and subject was used to the greatest possible extent.
1977 Lancet 28 May 1142/2 With stratification for hospital, age, and year of admission, the maximum-likelihood estimate of uniform risk ratio was 3·3.
Compounds
General attributive (chiefly in sense 2a, 6, 9), as stratification plane, stratification system, stratification theory, stratification variable, etc.
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1857 London, Edinb. & Dublin Philos. Mag. 4th Ser. 14 Suppl. 498 The stratification theory is in no way inconsistent with the occasional occurrence of ‘lenticular structure’ in the fragments of blue ice.
1884 A. Geikie in Nature 13 Nov. 30/1 These thrust-planes..could not be distinguished from ordinary stratification-planes.
1902 Proc. Royal Soc. London 69 399 On exhausting to the stratification-point, I could get no spectrum which did not show, in addition to hydrogen, also mercury.
1923 D. A. Mackenzie China & Japan (1994) xiv. 256 Some exponents of the stratification theory incline to regard Chinese religion as a stunted outcrop of animistic ideas.
1937 Amer. Antiq. 3 15 A supplementary one [sc. system of classification]..that cuts across the stratification system.
1974 H. M. Morris Sci. Creationism 113 A paraconformity..is difficult or impossible to distinguish from a normal stratification plane.
1995 E. Kallen Ethnicity & Human Rights Canada (ed. 2) Pref. p. xiii We will analyse the vertical Canadian mosaic, Canada's ethnic stratification system.
2014 R. B. Johnson & L. Christensen Educ. Res. (ed. 5) x. For example, if the stratification variable is gender, then the proportions of males and females will be in the sample will be the same as the proportions in the population.
This entry has been updated (OED Third Edition, December 2016; most recently modified version published online March 2022).
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