barbarism n.

mid-15c., "uncivilized or rude nature, ignorance or want of culture," from French barbarisme "barbarism of language" (13c.), from Latin barbarismus, from Greek barbarismos "foreign speech," from barbarizein "to do as a foreigner does," from barbaros (see barbarian

(n.)).

 Only of speech in Greek, Latin, and French; the sense extension to "uncivilized condition" took place in English. It is in English from 1570s as "offense against purity or style of language" (originally the use of foreign words in Latin and Greek); the meaning "an expression or word not in accord with the proper usage of a language" is from 1580s.