Top definition
Getting your friend’s boyfriend / girlfriend by chance, mistake, or intent. If by intent, your friend mustn’t know of the hook-up.

Originated in 1986, in the film Karate Kid II.



Yo man, don't box-mix me.

Look at that boxmixer, he is so depressed. I would hate to be a boxmixer. I just got boxmixed.
by popeyeman March 21, 2009
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