Reb vs Rebel

Reb and Rebel both are nouns.

Word	Noun	Adjective	Verb	Adverb
Reb	Yes	No	No	No
Rebel	Yes	No	No	No

As nouns, Reb and Rebel are synonyms defined as:

Reb and Rebel: `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

Other synonyms of Reb include greyback, Johnny, Johnny Reb.

Reb (noun)	Rebel (noun)
`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	`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