Cracker \Crack"er\ (kr[a^]k"[~e]r), n.

1. One who, or that which, cracks.

2. A noisy boaster; a swaggering fellow. [Obs.]

What cracker is this same that deafs our ears? --Shak.

3. A small firework, consisting of a little powder inclosed in a thick paper cylinder with a fuse, and exploding with a sharp noise; -- often called firecracker.

4. A thin, dry biscuit, often hard or crisp; as, a Boston cracker; a Graham cracker; a soda cracker; an oyster cracker.

5. A nickname to designate a poor white in some parts of the Southern United States. --Bartlett.

6. (Zo["o]l.) The pintail duck.

7. pl. (Mach.) A pair of fluted rolls for grinding caoutchouc. --Knight.

Source: Webster's Revised Unabridged Dictionary (1913)