Lex

имя существительное [латинский язык] закон Синоним(ы): law, rule

Большой англо-русский словарь

Lex

noun (plural leges) Etymology: Latin leg-, lex law

Merriam-Webster's Collegiate Dictionary

Lex

1. A lexical analyser generator for Unix and its input language. There is a GNU version called flex and a version written in, and outputting, SML/NJ called ML-lex. A version, by David Poole at Montana has been retargeted to Turbo Pascal 2. The lexical specification language for COPS.

Free Online Dictionary of Computing