Pronunciation (UK) IPA (key): /nɒkˈtɜː(r)nəl/ (US) IPA (key): /nɑkˈtɚnəl/ Audio (US)(file) Adjective Positive nocturnal Comparative more nocturnal Superlative most nocturnal When someone is nocturnal, they are active and awake at night. Owls are nocturnal animals. Wikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads