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