Named after the famous Great Dane; it is any dog the gets in the way of love making and flirting of all kind purposefully or inadvertently .
Guy: Man, I think I have blue-balls. I was about to get some last night, until her dog came in and started barking waking everyone up.

or

Guy: Man, I think I have blue-balls. I was about to get some last night, until her dog came in and wouldn't leave her alone

Guy 2: I'm sorry, damn Cock-blocking Scooby Doos
by rissie2q January 20, 2013
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