from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A Confederate soldier during the US Civil War (because of the grey uniforms).
- n. A louse.
- n. A local name for various grey birds.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a sandpiper that breeds in the Arctic and winters in the southern hemisphere
- n. a dowitcher with a grey back
- n. `Johnny' was applied as a nickname for Confederate soldiers by the Federal soldiers in the American Civil War; `greyback' derived from their grey Confederate uniforms
From grey + back. (Wiktionary)