A low-cut shirt, usually a v-neck, often with features such as one or more of the following: ruffles, sequins, lace, glitter, or other noticeable "flashy" elements. Often worn with jeans or, occasionally, a skirt, they are a figure-flattering yet relatively casual option for femmes or ladies looking to attract attention, be flirtacious, or express a mildly provocative style.

The slang appears to originate in Eastern Canada or the Maritimes.
"Are you going out with us tonight, Kate? You can borrow one of my bar tops."
by SciFiMagpie February 13, 2018
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