Lex is a short form of Alexander, the Greek name meaning "defender of men", and is also the Latin word for "law". Americans know it from Lex Luthor, Superman's archenemy, which gives the name a slightly villainous edge, and from Lex Barker, a screen Tarzan of the 1950s. As a given name Lex peaked at number 1524 in 2003 and ranks number 2322 in 2025.