Definition of "pentomino" []

• A polyomino made up of five squares. (noun)

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• "The Book Fest event will include pentomino puzzle activities."
• "If you're familiar with the game Blokus, the pieces given to each player in a game of Blokus consist of all unique polyonimoes from size one (monomino) through size five (pentomino)."
• "Cory Doctorow at 10:52 PM Thursday, Feb 17, 2011 Music of Minecraft: Deadmau5 test tracks on Soundcloud - Boing Boing pentomino yes, the video thumbnail is accurate."