c. 1600, "state of being environed" (see environ (v.) + -ment); sense of "the aggregate of the conditions in which a person or thing lives" is by 1827 (used by Carlyle to render German Umgebung); specialized ecology sense first recorded 1956.
1923, as a psychological theory (in the nature vs. nurture debate), from environmental + -ism. The ecological sense is from 1972. Related: Environmentalist (n.), 1916 in the psychological sense, 1970 in the ecological sense.
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<a href="https://www.etymonline.com/word/environmental">Etymology of environmental by etymonline</a>
Harper, D. (n.d.). Etymology of environmental. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/environmental