Phrase originating in Britain that is uttered by ravers/binge-drinkers when they are. Usually shouted repeatedly whilst loud electronica/techno/dance/rave music is blaring, and whilst the speaker is raving/dancing
"LET'S GO FUCKING MENTAL, LET'S GO FUCKING MENTAL, LET'S GO FUCKING MENTAAAAAAL!!!"

*smashes glass over own head rendering himself unconscious*
by Scekhcsy Foxmonk August 12, 2010
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