The crossword solution for the term LAW, IN LATIN is 'LEX'. Lex is a Latin word meaning law. It is derived from the Proto-Indo-European root *leǵ-s, which also gave rise to the English word 'LEGAL'. Lex is used in many LEGAL contexts, such as in the phrase lex talionis, meaning 'law of retaliation'. It is also used in the names of various LEGAL codes, such as the Lex Salica, a code of law in the Frankish Empire.