the quality of being rash and foolish; "trying to drive through a blizzard is the height of folly"; "adjusting to an insane society is total foolishness"
any of numerous small rodents typically resembling diminutive rats having pointed snouts and small ears on elongated bodies with slender usually hairless tails
a hand-operated electronic device that controls the coordinates of a cursor on your computer screen as you move it around on a pad; on the bottom of the device is a ball that rolls on the surface of the pad; "a mouse takes much more room than a trackball"