occlusionn.
/əˈkluːʒn/, U.S. /əˈkluʒ(ə)n/ 1.
a. Chiefly Science. The action of occluding something; the condition of being occluded; blocking, closing, obstruction; an instance of this.
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the world > space > relative position > closed or shut condition > [noun] > closing or shutting > stopping or blocking up
forbarringc1449
stopping1487
stoppage1540
obturation1583
obstipation1612
interclusion1623
occlusion1645
stopping up1671
blocking1706
clogging1846
choking1863
1645 J. Howell Epistolæ Ho-elianæ iii. xxix. 100 By the constriction and occlusion of the orifice of the Matrix.
1746 Philos. Trans. (Royal Soc.) 44 14 To explain the Manner of the Occlusion of the Eye.
1786 H. Lee in J. Sparks Corr. Amer. Revol. (1853) IV. 137 In agreeing to the occlusion of the navigation of the Mississippi.
1802 T. Jefferson Let. 16 Dec. in Papers (2012) XXXIX. 179 The occlusion of the port of N. Orleans by the Spaniards..was calculated to give great alarm through the US.
1881 A. Flint Treat. Princ. Med. (ed. 5) 187 Occlusion of the bronchi immediately connected with the atelectatic spots can be demonstrated.
1908 Osler's Mod. Med. V. 443 Occlusion signifies a complete closure of the intestinal lumen.
1937 Amer. Jrnl. Obstetr. & Gynecol. 33 39 When the occlusion is at the fimbriated end [of the fallopian tubes], simple release of adhesions may suffice to restore the patency of the tube (salpingolysis).
1946 A. Nelson Princ. Agric. Bot. vii. 152 The ovary is inserted at the bottom of the cup and well protected by occlusion within the hollow torus.
1947 Nucleonics Dec. 7/1 An endotracheal tube with occlusion cuff was inserted and clamped off.
1956 Jrnl. (Fairfax County, Va.) May 28 a6/2 It's conceivable that if he paused long enough in a typical I–95 occlusion he'd hear words that would whiten the hair of a bosun.
1961 D. M. Pillsbury et al. Man. Cutaneous Med. ii. 49 In acne the sebaceous gland may atrophy as a result of concomitant poral occlusion.
1988 Zool. Jrnl. Linn. Soc. 94 68 Control of light emission can only be effected by occlusion of the luminous face of the organ.
b. Medicine. Total or partial obstruction of a blood vessel, esp. by thrombosis; an instance of this.
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1850 Philos. Trans. (Royal Soc.) 158 158 Here, the metamorphosis by occlusion has affected the right primitive veins.
1899 T. C. Allbutt et al. Syst. Med. VI. 211 In some situations veins, whose rapid occlusion may cause serious lesions and symptoms, may be slowly plugged by a thrombus without manifest harm.
1929 S. A. Levine Coronary Thrombosis vii. 109 The point of occlusion was found in various locations anywhere along the course of the vessels from their orifices, as a result of extensive aortic disease, to the very small arterial branches.
1965 Clin. Sci. 29 124 The decrease of renal blood flow observed in the majority of subjects during and after pulmonary occlusion is difficult to explain.
1993 Brit. Jrnl. Surg. 80 194 Intra-arterial thrombolysis (IAT) was used as first-line treatment for 100 occlusions causing acute, subacute or chronic ischaemia.
c. figurative.
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1894 Atlantic Monthly Feb. 191/1 To the materialist,..such a conceptual idea is an occlusion, a stumbling-block, a mere figment.
1951 L. R. Hubbard Handbk. for Preclears 60/2 Occlusion of childhood and hallucinatory pictures of childhood are occasioned by telling the child what happened to him often and in detail. This knocks out the facsimile of the child and substitutes either occlusion or a false picture.
1980 Times Lit. Suppl. 20 June 716/3 An essential ingredient of Delphine, and indeed of all these novels, is the postponement or occlusion of sexual enjoyment.
1985 P. Fuller Images of God i. 7 He suffers from some stultifying occlusion of the imagination.
2. Chemistry.
a. The absorption and retention of a gas within the interstices of the crystal lattice of a metal or other solid.
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the world > matter > gas > [noun] > state of being pervaded by or charged with > retention of gas in pores of substance
occlusion1866
1866 T. Graham in Philos. Trans. (Royal Soc.) 156 423 It may be allowed to speak of this [power to absorb hydrogen at a red heat, and to retain that gas] as a power to occlude (to shut up) hydrogen, and the result as the occlusion of hydrogen by platinum.
1871 H. E. Roscoe Lessons Elem. Chem. (new ed.) xvii. 186 The fact that red-hot platinum and iron are porous for hydrogen may be explained by the absorption (or occlusion) of this gas on the one side of the metallic tube or plate and its evaporation at the other side.
1948 S. Glasstone Textbk. Physical Chem. (ed. 2) xiv. 1204 The occlusion of hydrogen by palladium..may well be an extreme case of combined activated adsorption and persorption.
1996 Earth & Planetary Sci. Lett. 141 315 (heading) Occlusion of noble gases (He, Ne, Ar, Kr, Xe) into synthetic magnetite at 500–1300°C.
b. The inclusion of any substance within the crystals of another. Also: spec. (a) the absorption of solvent or of soluble species within a precipitate; (b) the trapping of pockets of fluid within a growing crystal.
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the world > matter > chemistry > crystallography (general) > crystal (general) > crystal inclusions > [noun] > occlusion
occlusion1891
the world > matter > chemistry > chemical reactions or processes > [noun] > chemical reactions or processes (named) > precipitation > co-precipitation > occlusion
occlusion1891
1891 T. W. Richards in Proc. Amer. Acad. 26 259 Few experimenters seem to have realized that the occlusion of most metallic sulphates tends to decrease the amount of precipitate obtained.
1920 Chem. Abstr. 14 3029 (heading) The occlusion of lime and magnesia by ferric oxide.
1932 Jrnl. Physical Chem. 36 860 It has been a general custom in analytical chemistry to use the words, coprecipitation, carrying down, occlusion, inclusion and adsorption as collective names, meaning nothing else but..that impurities are carried down with or in a precipitate.
1966 E. M. Rattenbury Introd. Titrimetric & Gravimetric Anal. vii. 146 Sometimes water or mother liquor is imprisoned by occlusion.
1969 E. S. Gilreath Elem. Quantitative Chem. x. 138 Contamination by occlusion..can produce serious errors in gravimetric analysis.
1989 Nature 18 May 174/1 Active sites may also be generated by the incorporation of multivalent cations or occlusions of reactive metals.
1992 Science 17 Jan. 320 (caption) A horizontal arrow marks the N2/Ar ratio in the bubbles..when they became isolated from the liquid by occlusion in the ice.
3. Dentistry and Zoology. Closure of the jaws; contact between the teeth of the upper and lower jaws; the relationship between the upper and lower teeth when in contact; an instance of this.
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the world > life > the body > digestive or excretive organs > digestive organs > mouth > tooth or teeth > [noun] > arrangement or position of
dentition1849
dentelure1877
occlusion1880
proclination1924
1880 N. W. Kingsley Treat. Oral Deformities xxi. 525 In extreme pain (except in cases where the patient is suffering from periodontitis, when the occlusion of the jaws intensifies the suffering), the teeth are brought together with great force.
1904 V. H. Jackson Orthodontia 198 The opening of the bite in any manner with apparatus, if continued for a considerable time, is likely to prove detrimental to the occlusion.
1962 G. C. Blake & J. R. Trott Periodontol. xv. 156 In the European it is usual to find that during lateral movements to either side molar and pre-molar teeth of one side remain in occlusion, while contact is completely lost on the other side.
1974 F. J. Harty & D. H. Roberts Restorative Procedures Pract. Dentist xii. 167 It is very important that the occlusion is studied and corrected before any fixed or removable prosthesis is made.
1979 R. C. Fox in R. W. Fairbridge & D. Jablonski Encycl. Paleont. 429/2 Occlusion was alternate in the sense that each molar occluded within the embrasure between two successive molars on the opposite jaw.
1991 Saudi Med. Jrnl. 12 317/2 The frequently used Down's analysis was based on 25 untreated adolescents with ideal occlusions.
4. Phonetics. The momentary closure of the breath passage during the articulation of an orally released consonant, or of the mouth passage during the articulation of a nasal consonant.
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the mind > language > linguistics > study of speech sound > speech sound > speech sound by manner > [noun] > obstruent > partial or complete closure
closure1867
occlusion1906
stricture1943
1906 Mod. Lang. Rev. 1 iv. 346 ‘Occlusion’, was, if I remember aright, used by Wilkins in the seventeenth century, but this hardly justifies the employment of such a pedantic term instead of ‘stoppage’, ‘closure’, or ‘stop’.
1926 Germanic Rev. 1 i. 58 Here, ‘occlusion’ in the glottis does not mean glottal stop, but the partial occlusion in the articulation of voice sounds.
1935 J. S. Kenyon Amer. Pronunc. (ed. 6) 51 This initial contact for any sound that has contact is called the closure, or occlusion, and the end of the contact is called the opening, or release.
1966 B. Trnka Phonol. Anal. Standard Eng. (rev. ed.) ii. 11 In producing l, the tip of the tongue forms an occlusion against the alveolar ridge.
1986 Canad. Jrnl. Linguistics 31 248 When [w] combines with a coronal obstruent or nasal, the segment acquires a..labiovelar occlusion.
5.
a. Ophthalmology. The covering of an eye so as to prevent its use, esp. for the treatment of strabismus and amblyopia.
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the world > health and disease > healing > ophthalmology or optometry > [noun] > orthoptics
occlusion1920
orthoptics1934
1920 Brit. Jrnl. Ophthalmol. 4 146 (title) The influence of prolonged monocular occlusion in revealing errors of the muscle balance.
1962 J. W. Henderson in G. M. Haik Strabismus v. 111 For the eccentric fixator over 5 years of age, pleoptics rather than occlusion are thought to be the most acceptable method [of treating amblyopia].
1973 Nature 26 Jan. 288/2 The technique of monocular occlusion has long been used by ophthalmologists in the therapeutic treatment of such conditions as strabismus (squint) and amblyopia.
1986 Nursing Times 3 Dec. 46/1 I already had severe amblyopia in my squinting eye, and in spite of wearing glasses and extensive occlusion therapy, this did not improve.
b. The disappearance or blocking of something from view (as a result of a change in the observer's perspective, an obstruction in the line of sight, etc., or as a phenomenon in various types of image production); an instance of this.
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the world > physical sensation > sight and vision > invisibility > [noun] > being cut off from view by something interposed
occultation1882
occlusion1972
1972 J. J. Gibson in J. R. Royce & W. W. Rozenboom Psychol. Knowing vi. 220 The optical transition between what I call two ‘vistas’ of the world (as when an observer goes from one room to another) entails the progressive occlusion of some parts of the world and the disocclusion of others.
1983 A. Rosenfeld in O. D. Faugeras Fund. Computer Vision 174 Objects may even appear or disappear between one frame and the next, due to their occlusion or disocclusion (by the edges of the frame or by other objects) or due to noise.
1998 Vision Res. 38 2489/1 Much more [information about the world] is usually lost via occlusions by external objects along the observer's line of sight.
2005 J. Williats Making Sense of Children's Drawings ix. 183 At (d) the saucepan has been added, with the partial occlusion of the side edge of the table by the handle of the saucepan correctly represented.
6. Meteorology. The process by which the cold front of a rotating low-pressure system catches up the warm front, so that the body of warm air between the fronts is forced upwards away from the ground between wedges of cold air; (also) the occluded front so formed.
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the world > the earth > weather and the atmosphere > movements and pressure conditions > [noun] > uniform body of air > boundary of > overtaking of warm by cold front
occlusion1922
1922 J. Bjerknes & H. Solberg in Geofysiske Publikationer 3 6 No boundary surface results when both branches meet during the occlusion of the cyclone.
1922 J. Bjerknes & H. Solberg in Geofysiske Publikationer 3 7 The occlusion then assumes the character of a cold front with a rather narrow rain zone.
1944 E. W. Hewson & R. W. Longley Meteorol. Theoret. & Appl. xvi. 277 The rate of occlusion in several types of frontal depressions may be discussed qualitatively.
1955 W. J. Saucier Princ. Meteorol. Anal. ix. 270/1 The cold front overtakes the warm front, resulting in an occluded front (or occlusion).
1974 Encycl. Brit. Macropædia V. 394/2 There still is a belt of thick cloud and rain along the line of the old occlusion.
1998 Monthly Weather Rev. (U.S.) 126 2521 Unlike occlusions, for which the fronts slope in generally opposite directions, a frontal merger is characterized by fronts that slope in roughly the same direction.
This entry has been updated (OED Third Edition, March 2004; most recently modified version published online March 2022).
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