Originally, this was a dismissive nuclear reply to someone, suggesting that they leave you alone. Mainstream use has shortened the phrase from “Go lick Jim’s asshole; he likes that” to simply Go lick Jim’s asshole (GLJA) and expanded the meaning to include variations of non-compliance or disbelief - no way, dafuq, pound sand, kick rocks, GTFO, STFU, etc.
While arguing with my sister, I asked if she wanted BK. She told me to go lick Jim’s asshole.

Bro, I just won the Powerball.

Dude, go lick Jim’s asshole. You’re a fkn liar.
by The570Quinny January 12, 2021
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