v. to 'beef' with someone's mind; could be brainwashing, confusing, disorienting etc etc.

n. a 'mindbeef' (the act of mindbeefing); either 1. a tactic of confusing or 'psyching out' someone, or 2. (inf.) to skull-fuck; vigourous oral sex
Frank: I had sex with your mother last night.
Dave: Stop beefing with my mind!

(At the prison showers)
Bubba: You gettin' mindbeef'd faggot
Weiner doing time for income tax evasion: Gulp!
by Terry Deary May 29, 2005
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