A female friend, usually of lesser physical appeal, accompanying her attractive girlfriend in a social situation, like a bar or a dance hall. Will try to take down any approaching males hitting on her hot companion with negative, sarcastic or sometimes poisonous comments or remarks. It's the negative counterpart of the Wingman.
'Hey bro, check out the hottie at 9 o'clock. I think I'll invite her for a drink!'
'Yeah, we'd better watch out though. Looks like she's with a sidewhinner.'
'Yeah, we'd better watch out though. Looks like she's with a sidewhinner.'
by tbtorro July 20, 2018
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