(botany) The outer shell of a fruit or similar body. / (botany) One of the specialized bracts around the floret in grasses.

(mathematics) A proposition proved or accepted for immediate use in the proof of some other proposition.

(rare) A female given name

plural of lemma

(singular only, mathematics) A particular lemma that claims the existence of a particular isomorphism in a commutative diagram given certain other homomorphisms in the diagram.

(set theory) A proposition of set theory stating that every partially ordered set, in which every chain (i.e. totally ordered subset) has an upper bound, contains at least one maximal element.

plural of pumping lemma

(computer science) A lemma which states that for a language to be a member of a language class any sufficiently long string in the language contains a section that can be removed or repeated any number of times with the resulting string remaining in the language, used to determine if a particular language is in a given language class (e.g. not regular).

(category theory) Given a category 𝒞 with an object A, let H be a hom functor represented by A, and let F be any functor (not necessarily representable) from 𝒞 to Sets, then there is a natural isomorphism between Nat(H,F), the set of natural transformations from H to F, and the set F(A). (Any natural transformation 𝛼 from H to F is determined by what 𝛼_A( mbox id_A) is.)

(lexicography, rare) Any form of a lexeme that is not its lemma.