Lemma (l&ebreve_;mm&adot_;), n.; pl. L. Lemmata (-m&adot_;t&adot_;), E. Lemmas (-m&adot_;z). [L. lemma, Gr. lh^mma anything received, an assumption or premise taken for granted, fr. lambanein to take, assume. Cf. Syllable.] 1. (Math., Logic) A preliminary or auxiliary proposition demonstrated or accepted for immediate use in the demonstration of some other proposition, as in mathematics or logic.
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2. A word that is included in a glossary or list of headwords; a headword.
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