A bra slip is like a nip slip but only your bra shows. When u fix ur shirt and it goes up or down and ur bra awkwardly shows
Hailey: did u see kellie in the cafeteria today?

Sofia: ya she had a bra slip and everyone saw

Hailey: she doesn't care, she had a nice bra
by Who_cares_bitch April 6, 2014
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