labile, a.
(ˈleɪbɪl, -aɪl; formerly also ˈlæbɪl)
Also 5 labyl, 7 labil.
[ad. L. lābil-is, f. lābī to slip, fall, lapse: see -ile. Cf. F. labile.]
1. Liable or prone to lapse. † a. Prone to fall into error or sin; Theol. liable to fall from innocence (obs.). b. Of a fund, etc.: Lapsable.
| 1447 O. Bokenham Seyntys (Roxb.) 147 My labyl mynde and the dulnesse Of my wyt. 1678 Gale Crt. Gentiles III. 199 The supralapsarian Divines, who make man as labile the object of reprobation. 1740 Cheyne Regimen iv. 140 All Creatures being finite and free, must necessarily, by their Nature, be labile, fallible and peccable. 1894 Forum June 449 These funds are no more labile than any other form of trust or mortmain. |
† 2. Apt to slip away, slippery. lit. and fig. Obs.
| 1623 Cockeram, Labile, slipperie, unstable. 1654 Jer. Taylor Real Pres. 14 Now a man would think we had him sure; but his nature is labile and slippery. |
3. Prone to undergo displacement in position or change in nature, form, chemical composition, etc.; unstable. Now only in Physics and Chemistry.
| 1603 Florio Montaigne ii. xii. (1632) 340 Pithagoras [said] that each thing or matter was ever gliding and labile. 1654 Jer. Taylor Real Pres. §1 Wood..can..be made thin, labile and inconsistent. 1878 Foster Physic. ii. v. 363 More labile than tissue proteid and yet more stable than the circulating proteid. 1889 J. S. Burdon-Sanderson in Nature Sept. 26 Protoplasm..comes to consist of two things..of acting part which lives and is stable, and of acted-on part which has never lived and labile, that is, in a state of metabolism. 1894 Ld. Salisbury in Pop. Sci. Monthly Nov. 40 The genius of Lord Kelvin has recently discovered what he terms a labile state of equilibrium. 1947 New Biol. VII. 66 In both spring and winter rye the first seven initials to be developed at the growing point give rise to leaves under any combination of environmental factors so far tried. These are followed by about 18 ‘labile’ initials which may give rise either to leaves or flowers according to treatment. 1951 I. L. Finar Org. Chem. I. x. 170 When one tautomer is more stable than the other under ordinary conditions, the former is known as the stable form, and the latter as the labile form. 1970 Nature 4 Apr. 25/2 The other component of nitrogenase from the two bacteria has a molecular weight of about 40,000, two iron and two labile sulphide groups. |
4. Electr. Said of the application of a current by moving an electrode over an affected region instead of holding it firmly at one part.
| 1888 in Syd. Soc. Lex. 1893 A. S. Eccles Sciatica vi. 65 With the anode labile over the foot, leg, and thigh. 1896 Allbutt's Syst. Med. I. 369 The battery current labile over the affected muscles. |
Hence laˈbility, proneness to lapse, instability of form or nature. Now chiefly in scientific use.
| 1554 in Maitl. Club Misc. III. (1855) 65 The labilite and breuitie of tymes maneris and of men in this wale of teiris beand considerit. 1557 R. Edgeworth Sermons Pref. sig. {cross}3, I euer fearinge the labilitie of my remembraunce, vsed to pen my sermons. 1646 Gaule Cases Consc. 34 Vanity of Science, error of Conscience, lability of innocence. 1654 Jer. Taylor Real Pres. xi. §32. 247 Consistence or lability, are not essential to wood and water. 1740 Cheyne Regimen v. (1790) 218 But Sensibility and Intelligence, being by their Nature and Essence free must be labile, and by their Lability may actually lapse, degenerat [etc.]. 1810 Coleridge Lit. Remains (1838) III. 353 To the species water continuity and lability are essential. 1903 A. R. Wallace Man's Place in Universe xi. 207 Those peculiarities which are essential to life—extreme sensitiveness and lability. 1904 Jrnl. R. Microsc. Soc. 188 By combining these two methods there is induced a ‘nuclear lability’, which renders these eggs susceptible to the influence of carbon dioxide as a provocative of cleavage. 1924 J. G. A. Skerl tr. Wegener's Orig. Continents & Oceans 154 The frequently described ‘lability’ of the geosynclinals. 1942 Jrnl. Immunol. XLV. 164 The lability in formalin of any antigen studied must thus be determined. 1970 H. C. Shands Semiotic Approaches to Psychiatry xxiii. 395 Clinical observation often suggests that the emotional lability of the ‘schizophrenic’ is not only often less than, it is also sometimes greater than, that of the normal. 1973 J. M. Anderson Structural Aspects of Language Change 143 The holes in the phonological paradigm are characterized by a general condition of lability. |
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Add: [3.] b. Psychol. Emotionally or behaviourally unstable. Cf. volatile a. 4.
| 1934 in Webster. 1953 E. Jones Sigmund Freud I. ix. 188 His moods were certainly labile and when things were going well they could be markedly euphoric. 1984 S. Bellow Him with his Foot in his Mouth 127 He seemed to her unstable, off center. The term often used in Psychology Today was ‘labile’. |