A term used by fisherman, kayakers or those trying to enjoy other small watercraft to describe rude people on jet skis who are inconsiderate of others on the water.
The idiots on jet skies were like black flies annoying the fishermen in their small fishing boats.
by Sagittarian July 24, 2006
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The black cow flies at midnight means anything you want. Also used for guy code, "is your girlfriend, wife, significant other around"? This phrase is used to check if the coast is clear.

This phrase is also used to speak in code for any real day situation: is the black cow flying at midnight?

Examples: when you don't want people around to know what you are talking about.
Yo bro, the black cow flies at midnight?

Yup

Ok let me know when your girlfriend leaves.....
by Bigdogdaddy13 January 26, 2013
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