An acronym used in incel (involuntary celibate) communities and blackpill-adjacent online spaces, standing for
Elliot Rodger (often stylized as "E.R." or simply "ER").
Elliot Rodger was the perpetrator of the 2014 Isla Vista killings, a
misogynistic mass murder-suicide where he targeted women and others he blamed for his romantic/sexual rejection. In incel slang, "ER" refers to him directly, while phrases like "going ER," "pull an ER," or "go ER" euphemistically describe committing (or fantasizing about committing) similar acts of mass violence—typically murder-suicide—as "retribution" against perceived societal rejection, women, or "Chads/normies."
Person A: "Another
rejection today, life is over. Might as well rope."
Person B: "Bro, don't LDAR forever. If you're truly
blackpilled, just go ER and
make them pay. Saint Elliot did it right."