Word parts bird + brain Pronunciation (UK) IPA (key): /ˈbɜː(r)d.breɪn/ (US) IPA (key): /ˈbɚd.breɪn/ Audio (US)(file) Noun Singular birdbrain Plural birdbrains (informal) A birdbrain is someone who is not intelligent. Wikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads