Pronunciation (UK) IPA (key): /ˈmɛməʊ̯/ (US) IPA (key): /ˈmɛmoʊ̯/ Audio (UK)(file) Noun Singular memo Plural memos (countable) (informal) A memo is a short message or note. Synonym: memorandum I have an urgent memo from the CEO.Wikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads