ˌplano-ˈconvex, a.
[f. as prec. + convex.]
1. Having one surface plane and the opposite one convex: chiefly of lenses; also of natural formations, as parts of plants or animals, or other objects.
| 1665 Hooke Microgr. Pref. f j, I fixt also with wax a pretty large plano Convex Glass. 1693, 1807 [see prec.]. 1810 D. Stewart Philos. Ess. ii. i. vii. 330 In wooded scenes, the plano-convex mirrour, which was Mr. Gray's companion in all his tours, has a pleasing effect. 1830 Lindley Nat. Syst. Bot. 75 Cotyledons plano-convex. 1884 F. J. Britten Watch & Clockm. 102 Achromatic glass with two plano-convex lenses. |
b. Of a crystal: Having some faces plane and others convex.
| 1805–17 R. Jameson Char. Min. (ed. 3) 209 Plano-convex..when the faces are partly straight and partly uneven, as in the diamond. |
2. Having a flattened convex form.
| 1843 J. G. Wilkinson Swedenborg's Anim. Kingd. I. i. 21 The tongue's upper surface is plano-convex. 1845 Lindley Sch. Bot. vi. (1858) 83 Receptacle plano-convex, paleaceous. |