From Longman Dictionary of Contemporary Englishsonnyson‧ny /ˈsʌni/ noun old-fashioned spoken CHILDMANused when speaking to a boy or young man who is much younger than you Now you listen to me, sonny.
Examples from the Corpus
sonny• Come on, sonny, it's worth that.• I think we can afford it more than you, sonny.Origin sonny (1800-1900) son 