From The Collaborative International Dictionary of English v.0.48:
Spud \Spud\ (sp[u^]d), n. [Cf. Dan. spyd a spear.]
1. A sharp, narrow spade, usually with a long handle, used by
farmers for digging up large-rooted weeds; a similarly
shaped implement used for various purposes.
[1913 Webster]
My spud these nettles from the stone can part.
--Swift.
[1913 Webster]
2. A dagger. [Obs.] --Holland.
[1913 Webster]
3. Anything short and thick; specifically, a piece of dough
boiled in fat. [Local, U.S.]
[1913 Webster]
4. A potato. [Colloq.]
[Webster 1913 Suppl.]