Longman Dictionary of Contemporary English - cookie

~ n 1 especially AmE a flat, dry, sweet cake usually sold in packets; biscuit (1) BrE  (Karen had a glass of milk and a cookie.) 2 tough/smart cookie informal someone who is clever, successful, and strongly defends what they believe in 3 that's the way the cookie crumbles informal used when something unpleasant has happened to say that you must accept things the way they are, even though you do not like it 4 AmE old-fashioned an attractive young woman 5 ScotE a bun (1)