1.a
suffix occurring as the final element in informal shortenings of
nouns ( ammo; combo; condo; limo; promo ); -o, also forms nouns, usually derogatory, for persons or things exemplifying or associated with that specified by the base
noun or
adjective ( cheapo; pinko; sicko; weirdo; wino ). 2.a suffix occurring in colloquial noun or adjective derivatives, usually grammatically isolated, as in address: cheerio; kiddo; neato; righto.
Origin: perhaps orig. the interjection O, appended to words as in
def 2; as a derivational suffix reinforced by clipped forms of words with
-o- as a linking element (e.g.,
photo,
stereo), by Rom nouns ending in
o, and by personal nouns such as
bimbo and
bozo, of obscure origin
