A math proposition is a statement that can be proven or disproved using mathematical principles. The three crossword solutions for the term MATH PROPOSITION are LEMMA (5 letters), THEOREM (7 letters), and AXIOM (5 letters). A lemma is a lesser known THEOREM that is used as a stepping stone to prove a larger THEOREM. A THEOREM is a statement that has been proven to be true through mathematical reasoning. An AXIOM is a statement that is accepted as true without proof.