-o

1) aff. a suffix occurring as the final element in informal shortenings of nouns (ammo; combo; promo); -o also forms nouns, usu. derogatory, for persons or things exemplifying or associated with that specified by the base noun or adjective (pinko; weirdo; wino)

2) aff. a suffix occurring in informal noun or adjective derivatives, usu. grammatically isolated, as in address:

kiddo; neato; righto[/ex]