 Lemma (mathematics)

A theorem that is not very important on its own, often an intermediate step to proving something that the author feels deserves the name "theorem".

In mathematics, a lemma is a proven statement or proposition that serves as a stepping stone toward the proof of a larger theorem. Essentially, it is an intermediate result that helps simplify the proof process for more complex results. The use of lemmas is common in various branches of mathematics, including algebra, analysis, and topology. They are often named to honor mathematicians or to describe their purpose. For example, “Zorn's Lemma” in set theory is used to prove several important results.