← BackshareGuesskiddo/ˈkɪdoʊ/nounA friendly or affectionate term for a child or younger person.The coach patted him on the back and said, 'Nice game, kiddo.'She smiled at the little girl and said, 'You did great, kiddo.'Come on, kiddo, time to put on your jacket.SynonymskidchildyoungsterAntonymsadult