tercine Bot.
(ˈtɜːsɪn)
[= F. tercine (Mirbel 1828), f. F. tiers, tierce, or L. tertius third: see -ine1.]
A third integument supposed by some to occur in certain ovules: cf. primine.
| 1832 Encycl. Brit. (ed. 7) V. 52 note, The extensible side of the secundine, and even of the tercine or nucleus, soon ceases to increase. 1861 Bentley Man. Bot. (1870) 322 The embryo-sac is surrounded by a thin layer of cells, which has received the name of tercine. |