Bot. [= 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.

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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.

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1861.  Bentley, Man. Bot. (1870), 322. The embryo-sac is surrounded by a thin layer of cells, which has received the name of tercine.

3