n: When someone is sporting substantially sizeable breasts within the confines of a much smaller boulder holder, the "overspillage" gives the visual impression of four boobs smuggled under their t-shirt. i.e.. quad knocks
"no madam, I wouldn't advise purchasing our brasier in a 34B when you are quite clearly a 34DD, one wouldn't want to accuse you of having quad knocks now, would they?"
by coined the phrase quad knocks January 4, 2016
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