"love of humankind, especially as evinced in deeds of practical beneficence and work for the good of others," c. 1600, from Late Latin philanthropia, from Greek philanthrōpia "kindliness, humanity, benevolence, love to mankind" (from gods, men, or things), from philanthrōpos (adj.) "loving mankind, useful to man," from phil- "loving" (see philo-) + anthrōpos "mankind" (see anthropo-). Originally in English in the Late Latin form; the modern spelling in English is attested from 1620s.
word-forming element meaning "one who does or makes," also used to indicate adherence to a certain doctrine or custom, from French -iste and directly from Latin -ista (source also of Spanish, Portuguese, Italian -ista), from Greek agent-noun ending -istes, which is from -is-, ending of the stem of verbs in -izein, + agential suffix -tes.
Variant -ister (as in chorister, barrister) is from Old French -istre, on false analogy of ministre. Variant -ista is from Spanish, popularized in American English 1970s by names of Latin-American revolutionary movements.
<a href="https://www.etymonline.com/word/philanthropist">Etymology of philanthropist by etymonline</a>
Harper, D. (n.d.). Etymology of philanthropist. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/philanthropist