Pronunciation (UK) IPA (key): /ˈhɪd.iː.ʌs/ (US) IPA (key): /ˈhɪd.i.əs/ Audio (US)(file) Adjective Positive hideous Comparative more hideous Superlative most hideous When someone is hideous, it means the person is very ugly. Medusa was a hideous monster.Wikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads