| 释义 |
basal, a. (n.)|ˈbeɪsəl|
[f. base n. + -al1.]
A. adj.
1. Pertaining to, situated at, or forming the base. In Bot. Situated at the base of the ovary. basal plane and basal cleavage in Cryst.: one parallel to the lateral or horizontal axis.
1828Kirby & Sp. Entomol. III. xxxii. 330 The elytra have a basal gibbosity. 1845Darwin Voy. Nat. xii. (1879) 254 Geologising the basal parts of the Andes. 1870Hooker Stud. Flora 314 Amaranthaceæ ..ovules..basal.
2. fig. Fundamental.
1865Bushnell Vicar. Sacr. iii. v. (1868) 330 A much deeper and more nearly basal office. 1883H. Drummond Nat. Law in Spir. W. 378 Classification should rest on the most basal characteristics. 1918F. Wood-Jones Probl. Man's Ancestry 34 A being, whose body is replete with features of basal mammalian simplicity. 1963Publishers' Weekly 2 Sept. 44/2 To what extent are available paperback books adequate as compared with basal readers and early reading textbooks.
3. Comb., basal anæsthesia, administration of a light but long-acting anæsthetic which may be supplemented when necessary during an operation by a deeper short-acting anæsthetic; so basal anæsthetic; basal area, (a) the area situated at or forming the base; spec. in Ecol. (see quot. 1962); (b) Forestry, the area of the cross-section of a tree at a height of 4·5 feet above the ground, or the sum of such areas; basal complex Geol. = basement complex; basal conglomerate Geol., a conglomerate forming the lowest of a particular series of strata; basal cover Ecol. = basal area (a); basal ganglion, a ganglion situated at the base of the cerebrum (Cent. Dict. 1889); esp. in pl. basal ganglia, the thalamus, lentiform, and caudate nuclei considered as a group; basal granule, a granule found at the base of a flagellum or cilium in certain protozoa; basal metabolism, the metabolism of an organism in a fasting and resting state; so basal metabolic rate (see quots.); basal narcosis (see quots.); cf. basal anæsthesia; basal-nerved, a., ‘with nerves all springing from the base of the leaf’ (Gray Bot. Text-bk.); basal rot Hort. (see quot. 1954).
1934H. W. Featherstone in Brit. Med. Jrnl. 24 Feb. 322/2 The pioneer work in basal anaesthesia. Ibid. 326/1 Basal anaesthetics are a boon to patients.
1610W. Folkingham Art of Survey ii. viii. 62 Multiply the Basall Area by 6. 1895W. Schlich Man. Forestry iii. i. 46 The sample tree should show a basal area which corresponds exactly to the mean section of the class. 1938J. R. Carpenter Ecol. Gloss. 39 Basal area, (1)..The sum of the basal areas of trees in a forest stand is the basal area of the stand. (2)..Ground cover, basal cover. 1962H. Hanson Dict. Ecol. 43 Basal Area..the surface of the soil actually covered or occupied by a plant, especially the basal part, as compared to the full spread of the herbage.
1897Basal complex [see basement 1].
1900Geol. Mag. VII. 564 On the western shore of Ullswater..a good section has recently been exposed of the basal conglomerates variously ascribed to the Old Red or lowermost Carboniferous age.
1923J. T. Sarvis U.S. Dept. Agric. Bull. MCLXX. 20 Basal cover, as used here, means the extent of ground surface actually covered by plants after the foliage has been removed by grazing or clipping.
1913Cunningham's Text-bk. Anat. (ed. 4) 637 (heading) Basal Ganglia of the Cerebral Hemisphere. 1945New Biol. I. 82 Deep seated primitive components of the brain which include..the basal ganglia.
1920I. F. & W. D. Henderson Dict. Scientific Terms 28/2 Basal granule. 1951New Biol. XI. 114 Beneath the pellicle [of paramecium] the cilia connect with small round bodies known as basal granules or kinetosomes.
1922Jrnl. Amer. Med. Assoc. LXXVIII. 1887/2 (title) Correlation of Basal Metabolic Rate with Pulse Rate and Pulse Pressure. Extreme deviations from the normal basal metabolic rate are accompanied by..alterations in other functions. 1951M. Abercrombie et al. Dict. Biol. 138 In man, basal metabolic rate (B.M.R.) is expressed as the output of Calories per square metre of body surface per hour. 1952New Biol. XIII. 64 The standard index of the latter [i.e. the metabolism of the body] being the ‘basal metabolic rate’ (B.M.R.), which is essentially the rate at which oxygen is consumed by the body when it is in a resting condition.
1914Jrnl. Biol. Chem. XIX. 239 (title) Basal metabolism and creatinin elimination. 1920Lancet 7 Aug. 289/2 Basal metabolism—i.e., the metabolism of the individual during complete muscular repose, where a period of twelve hours had been allowed to elapse since taking the last meal. 1963M. McCarthy Group xiii. 303 The result of her basal metabolism [test] seemed to have restored her natural optimism.
1935Brit. Jrnl. Anaesthesia XIII. 15 This preliminary narcosis, or basal narcosis as it has been called. 1938Encycl. Brit. Bk. of Year 39/1 ‘Basal narcosis’..means the giving, at various times before the anaesthetic itself, of a sedative or hypnotic drug, which will reinforce the action of the gas.
1896Daily News 15 Apr. 715 Dr. Crawford [spoke] on basal rot. 1950N.Z. Jrnl. Agric. Feb. 176/2 The lily is subject to certain diseases; the most common are leaf spot..and basal rot (fusarium). 1954A. G. L. Hellyer Encycl. Garden Work 18/1 Basal rot, a name rather loosely applied to several quite distinct diseases which all attack bulbs, causing a decay of the base of the bulb... The decay is caused by fungal attack.
B. as n. A basal part; spec. one of the basal plates encircling the stem of the crinoids.
1620W. Folkingham Brachigraphy sig. A 6v, The third are Basals, falling from the Head of the Line, and landing below the Foot. 1877Huxley Anat. Inv. An. ix. 589 The basals coalescing into the rosette are hidden by the first radials. 1881Nature 4 Aug. 305 Those species of Pentacrinus in which the basals form a complete ring.
▸ basal pinacoid n. Crystallogr. a plane or face that intersects the principal or c axis and is parallel to both a and b axes; a crystal form or solid figure containing two such planes or faces parallel to each other.
1858J. Nicol Elem. Mineral. i. 20 In these prisms the principal axis is supposed to be prolonged indefinitely, or to be unbounded. Where it is very short and the lateral axes infinite, the *basal pinacoid is formed, consisting merely of two parallel faces. 1885Amer. Naturalist 19 798 Twins are not uncommon, the twinning plane being the basal pinacoid. 1959C. S. Hurlbut Dana's Man. Min. (ed. 17) ii. 96 Unlike the basal pinacoid of the orthorhombic system, it [sc. that of the monoclinic system] is not perpendicular to the c axis. 1984Micropaleontology 30 35/1 Wall of..aragonite (orthorhombic crystal form of calcium carbonate), the hexagonal prisms with c-axis normal to the wall surface, and basal pinacoid parallel to the surface. |