'not bad' definitions:

Definition of 'not bad'

(from WordNet)
adjective
Very good; "he did a bully job"; "a neat sports car"; "had a great time at the party"; "you look simply smashing" [syn: bang-up, bully, corking, cracking, dandy, great, groovy, keen, neat, nifty, not bad(p), peachy, slap-up, swell, smashing]

Synonyms of 'not bad'

From: Moby Thesaurus