Pronunciation: ' zo ̇ rnz-, ' tso ̇ rnz-
Function: noun
Etymology: Max August Zorn † 1993 German mathematician
Date: circa 1950
: a lemma in set theory: if a set S is partially ordered and if each subset for which every pair of elements is related by exactly one of the relationships “ less than, ” “ equal to, ” or “ greater than ” has an upper bound in S, then S contains at least one element for which there is no greater element in S ― compare AXIOM OF CHOICE