uggo in English dictionary uggo Meanings and definitions of "uggo" (slang) very ugly, of absolute ugliness. (slang) An ugly person. adjective (slang) ugly noun (slang) An ugly person. more Grammar and declension of uggo uggo ( comparative more uggo, superlative most uggo) uggo ( plural uggos) uggo (comparative more uggo, superlative most uggo) uggo (plural uggos) more Sample sentences with "uggo" Declension Stem Try again Authors