a subsidiary proposition that is assumed to be true in order to prove another proposition
"The mathematician used the lemma as a subsidiary proposition to establish the validity of his main theorem."
the lower and stouter of the two glumes immediately enclosing the floret in most Gramineae
"The botanist carefully examined the lemma, noting how its robust structure protected the delicate floret within the grass spikelet."
the heading that indicates the subject of an annotation or a literary composition or a dictionary entry
"The scholar carefully copied the lemma from the ancient manuscript to ensure he was referencing the correct headword in his translation."
A proposition proved or accepted for immediate use in the proof of some other proposition.
"The hard lemma protects the delicate grain inside the ear of corn."
The outer shell of a fruit or similar body.
In plain English: A lemma is a word form that appears at the beginning of an entry in a dictionary to show its base shape before adding endings for grammar or tense.
"The mathematician spent hours proving this lemma before tackling the larger theorem."
Usage: In everyday contexts, lemma is rarely used outside of mathematics and logic to describe an auxiliary statement needed to prove another theorem. Avoid confusing it with "lemma" as a biological term for the husk of grain unless specifically discussing botany.
A female given name
"After years of searching, they finally found a woman named Lemma living in the small village."
The word lemma comes from the Ancient Greek lêmma, which originally meant "premise" or "assumption." It is derived from a verb meaning "to take," reflecting how this concept was adopted into English.