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2.
When applied to girls: the quality of being unaware of - or otherwise unaffected by - blatant perving.
Gavin: (staring at Karen's breasts) Wow you have beautiful eyes.
Karen: Aw, you're so sweet.
Onlooker: Karen is totally impervious.
by PearlFly January 28, 2013
 
1.
im-pur-vee-uhs
not permitting penetration or passage; impenetrable, incapable of being injured or impaired:
The coat is impervious to rain, wear, and tear.
by Dani W June 16, 2008