A lemma is a proven statement or proposition that is used as a stepping stone to prove a larger theorem. In mathematics, lemmas help simplify complex proofs by breaking them down into more manageable parts. They are often considered intermediate results that support the main argument. In addition to mathematics, the term "lemma" is also used in linguistics, where it refers to the base form of a word. For example, the lemma for the verb "running" is "run." This helps in organizing and categorizing words in dictionaries and language studies, making it easier to understand their meanings and uses.