Available for anyone to obtain, claim, decide, or win.(adjective)
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Use "up for grabs" in a sentence
"I heard one of the football crowd telling policemen that it was a girl who had stolen the coach from outside the pub where they had pulled up for some refreshment; a girl who had yelled that there was free beer at the party along the road, a girl - 'a bit of all right ', 'a knock-out'-who'd said she was up for grabs for the quickest pair of boots after her into the garden."
"A $25,000 Pepsi Refresh Grant is up for grabs to the 10 communities that receive the most online votes by May 31."