An inflammatory term for someone who is acting weird; i.e. freakish, gross, annoying or overreacting to little things.

Also used as a generic insult with no real meaning other than to offend.

Used in a multitude of forms.
"Look at Andrew over there trying to flirt, what a grebe."

"Who's the fucking grebe who stole my wallet?"

"Dude, he doesn't want to stab us, he doesn't even know us. Stop grebin' out."
by Jonny22 September 14, 2011
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A company that produced radio equipment in the 1920's. They are well-known for the Grebe Synchrophase reciever.
The Grebe Synchrophase was an attempt at simplifying the three-dial tuning system that was common at the time.
by BlastMaster June 06, 2003
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Beth: fuck all them grebes!!

Sam: omg dude i know GREBES they're everywhere!!!
by lawlasaurusrex March 11, 2011
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