Etymology: late Old English fals adjective and noun, < Latin falsus false (neuter falsum , used substantively in sense fraud, falsehood), originally past participle of fallĕre to deceive; compare Old Norse fals noun. The adjective is found in Old English only in one doubtful instance (see sense A. 13); its frequent use begins in the 12th cent., and was probably due to a fresh adoption through the Old French fals, faus (modern French faux = Provencal fals, Spanish, Portuguese, Italian falso). The continental Germanic languages adopted the word in an altered form: Middle High German valsch, modern German falsch (compare Old High German gifalscôn to falsify), Old Frisian falsch, Dutch valsch, late Icelandic (15th cent.) falskr, Danish, Swedish falsk. The etymological sense of Latin falsus is ‘deceived, mistaken’ (of persons), ‘erroneous’ (of opinions, etc.). The transition to the active sense ‘deceitful’ is shown in phrases like falsa fides ‘breach of trust, faithlessness’, where the noun has a subjective and an objective sense. In modern English the sense ‘mendacious’ is so prominent that the word must often be avoided as discourteous in contexts where the etymological equivalent in other Germanic languages or in Romanic would be quite unobjectionable. Some of the uses are adopted < French, and represent senses that never became English.