▪ I. involute, a. and n.
(ˈɪnvəl(j)uːt)
[ad. L. involūt-us, -um, pa. pple. of involvĕre to roll in or up, involve.]
A. adj.
1. Involved; entangled; intricate; † hidden, obscure (obs.).
| 1669 Gale Crt. Gentiles i. iii. x. 101 They import an involute Speech or obscure question. 1690 Norris Beatitudes (1692) 10 Earthly-mindedness..was really forbidden according to the more retired and involute Sense of the Law. 1837 Carlyle Diam. Neckl. xvi. in Misc. Ess. (1872) V. 190 This most involute of Lies is finally winded off. a 1849 Poe Murders in Rue Morgue Wks. 1865 I. 179 ¶2 The possible moves [in chess] being not only manifold, but involute, the chances of such oversight are multiplied. 1889 Longm. Mag. Oct. 590 We all know good novels which are complex, involute, tortuous. |
2. Rolled or curled up spirally; spiral; spec. in Conch. Having the whorls wound closely round the axis, and nearly or wholly concealing it.
| 1661 Lovell Hist. Anim. & Min. Introd., III. Fishes, which are, I. Marine..or testaceous, and are turbinate, which are either involute, as the Nautilus..or orbicular, as the Welke. 1828 Stark Elem. Nat. Hist. II. 62 Bulla..body behind covered by an external oval involute shell. 1851–6 Woodward Mollusca 77 Shell placed vertically in the posterior part of the body, with the involute spire towards the ventral side. 1856–8 W. Clark Van der Hoeven's Zool. I. 389 Mouth with involute spiral tongue, composed of protracted maxillæ. |
3. Bot. Rolled inwards at the edges.
| 1760 J. Lee Introd. Bot. iii. xvi. (1765) 206 Involute, rowled in; when their lateral Margins are rowled spirally inwards on both sides. 1806 J. Galpine Brit. Bot. 40 L[eaves] involute, pungent. 1830 Lindley Nat. Syst. Bot. 144 Entire petals involute in æstivation. 1880 Gray Struct. Bot. iv. §2. 133 Leaves are as to the mode of packing..Involute, both margins rolled toward the midrib on the upper face. |
4. Geom. † involute figure or curve: = B. 2. Obs. Of a tooth in a cog-wheel: Having its working face in the form of an involute.
| 1706 Phillips, Involute and Evolute Figures. 1796 Hutton Math. Dict. I. 642/2 Involute Figure or Curve, is that which is traced out by the outer extremity of a string as it is folded or wrapped upon another figure, or as it is unwound from off it. 1884 F. J. Britten Watch & Clockm. 125 Wheels with involute teeth..are now rarely used. |
B. n.
1. Something involved or entangled. rare.
| 1845 De Quincey Susp. de Prof. i. Wks. 1863 XIV. 13 Far more of our deepest feelings..pass to us as involutes (if I may coin that word) in compound experiences incapable of being disentangled, than ever reach us directly. 1850 ― Ibid. 121 One of those many important cases which elsewhere I have called involutes of human sensibility. |
2. Geom. A curve such as would be traced out by the end of a flexible inextensible string if unwrapped (being still kept stretched) from a given curve in the plane of that curve; the locus of a point in a straight line which rolls without sliding on a given curve. Correlative to evolute.
| 1796 Hutton Math. Dict. I. 642/2 The Involute of a cycloid, is also a cycloid equal to the former. 1879 Thomson & Tait Nat. Phil. I. i. §17 If a flexible and inextensible string be fixed at one point of a plane curve, and stretched along the curve, and be then unwound in the plane of the curve, its extremity will describe an Involute of the curve. 1881 R. Routledge Science ii. 44 Apollonius treated also of involutes and evolutes. Ibid. ix. 208 Huyghens..discovered another curious property of the cycloid, and introduced a new idea into geometry, namely, that of the involutes. |
Hence ˈinvolutely adv., in an involved manner.
| 1681 H. More Exp. Dan. vi. 226 The sense is very coherent with what follows..which contains though something involutely and contractedly both the first and second Resurrection. |
▪ II. involute, v.
(ˈɪnvəl(j)uːt)
[Back-formation from involuted a.]
intr. a. ‘To return to a normal condition’ (Cent. Dict. Suppl.). b. To undergo involution (sense 4). Hence ˈinvoluting ppl. a.
| 1904 Buck's Handbk. Med. Sci. (rev. ed.) VII. 782/2 A circular scaly pink patch that spreads peripherally with a pinkish border, and clears up or involutes in the central portion. 1910 Practitioner July 106 The uterus had involuted normally. 1968 Amer. Jrnl. Obstetr. & Gynecol. CII. 33/1 Deeper arteries and veins contract and are compressed from without by the involuting muscle mass of the uterus. 1971 Jrnl. Insect Physiol. XVII. 857 These..glands reach the peak of their metabolic and synthetic activity shortly before rapidly involuting, leaving only a small remnant. |