Word parts observe + -er Pronunciation (US) IPA (key): /əbˈzɝvɚ/ or /ɑb-/ (UK) IPA (key): /əbˈzɜːvə/ or /ɒb-/ Audio (US)(file) Noun Singular observer Plural observers (countable) An observer is somebody who watches something. Wikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads