involucre
(ˈɪnvəl(j)uːkə(r))
[a. F. involucre (1545 in Hatz.-Darm.), ad. L. involūcrum.]
1. That which envelops or enwraps; a case, covering, envelope; spec. in Anat., a membranous envelope, as the pericardium.
| 1578 Banister Hist. Man i. 25 Pericardon (whiche is the Inuolucre of the hart). 1822–34 Good's Study Med. (ed. 4) I. 29 The involucres of the teeth are their gums, membranes, and sockets or alveoli. |
| fig. 1873 Earle Philol. Eng. Tongue (ed. 2) §196 The verb is the central representative and focus of that predicative force..which in the interjection is wrapped round and enfolded with an involucre of emotion. 1898 Month June 600 To distinguish the emotional substance of religion from its intellectual involucre. |
2. Bot. A whorl or rosette of bracts surrounding an inflorescence, or at the base of an umbel.
Also b. In ferns, sometimes applied to the indusium. c. In liverworts, a sheath of tissue surrounding the female sexual organs. d. In fungi, the velum. partial involucre = involucel. See also involucrum 2.
| 1794 Martyn Rousseau's Bot. v. 56 This set of small leaves or folioles is called the involucre. 1800 Asiatic Ann. Reg., Misc. Tr. 165/1 Flowers..in umbells..Involucre many leaved, the leaves toothed. 1845 Lindley Sch. Bot. i. (1858) 11 When many bracts are collected in a whorl round several flowers they form an involucre. 1861 Miss Pratt Flower. Pl. VI. 146 The indusium.. in some few of our native species, as in the Filmy Ferns,..is cup-shaped,..it is then often called an involucre. 1875 Bennett & Dyer Sachs' Bot. 303 The surrounding tissue of the thallus divides repeatedly and grows into an involucre which is arched upwards and through which the elongating sporogonium afterwards pushes its way. Ibid. 306. |
3. Zool. = involucrum 3.