1803, "the practice or exercise of brutality," from brutal + -ism. In the arts, 1953 in reference to a style characterized by deliberate crudity and exposed structure. Brutalist is from 1934 in literature.
mid-15c., "bestial, pertaining to or resembling an animal" (as opposed to a man), from Old French brutal, from Latin brutus (see brute (adj.)). Of persons, "unintelligent, unreasoning" (1510s); "fierce, savage, cruel, inhuman, unfeeling" (1640s). Related: Brutally.
word-forming element making nouns implying a practice, system, doctrine, etc., from French -isme or directly from Latin -isma, -ismus (source also of Italian, Spanish -ismo, Dutch, German -ismus), from Greek -ismos, noun ending signifying the practice or teaching of a thing, from the stem of verbs in -izein, a verb-forming element denoting the doing of the noun or adjective to which it is attached. For distinction of use, see -ity. The related Greek suffix -isma(t)- affects some forms.
<a href="https://www.etymonline.com/word/brutalism">Etymology of brutalism by etymonline</a>
Harper, D. (n.d.). Etymology of brutalism. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/brutalism