0 a thin, flat, hard biscuit, especially one eaten with cheese
1 a paper tube with small toys, small pieces of sweet food, etc. inside, that is covered with bright paper and makes a short, sharp sound when both ends are pulled:
2 a person or thing that is very good or has a special exciting quality:
She's written five books, and every one is a cracker.
3 a hard, dry, thin piece of baked bread