It seems to start mainly from Ancient Greece but has got as far as modern slang where it has been defined (urban dictionary) as another term for fag or faggot; used to hate on any person looking, acting, or being accused of being a homosexual. As in “Noah your such a fig.” The same source defines it as an acronym for “Female Identified Gay” A woman who identifies as a gay man and is not trans. A woman who is a gay man on the inside. Looking back at the history however there is even more:
“Gathering from the vine was like gathering figs, gathering testicles, gathering female fertility, gathering what is ripe and full of orge, gathering anger. The relation of fertility to both eras and anger allows for the metaphorical transfer of the rules of viticulture, fig gathering, heterosexuality, and homosexuality to processes of anger and punishment and makes punishment itself an analogue to sexual intercourse.
The Athenians had a number of fig-related words that could be used to insult those who misspent their erotic passions. In the Peace (1351), sukologein and sukazein are used to describe excessive homosexual intercourse. In another play Cleon is essentially accused 6f) being a homosexual rapist with a word that means “squeezing figs” (aposukazein, Kn. 259). He treats other people’s “testicles” too aggressively and too lustily. Negative forms of sexual behavior included not only “fig squeezing” (aposukazein) but also “fig gathering” (psenizein), another euphemism for homosexual contrectation.’’3 Cleon violated the norms of eras by acting too aggressively.
But how did the sycophant, who “pointed out figs,” violate the norms for standard use of the passions? According to Xenophon, the vine is supposed to point out to the farmer which fruits to pick and only those. There is therefore a right time and method for the exposure of ripe figs or of orge. There were rules against improper exposure in the sexual context. According to Henderson, the desire to “expose what should be hidden” was a fundamental part of sexual aggression. Calling attention to one’s opponent’s genitals was an act of violence, and according to Henderson, “references to testicles in Aristophanes almost always occur in threats (to rip out someone’s testicles) or in violent erotic advances (seizing the testicles in preparation for sexual contact) (e.g., Clouds 713, Birds 442).”
From the book “The World of Prometheus: The Politics of Punishing in Democratic Athens” By Danielle S. Allen