Λλ ⟵ {\displaystyle \longleftarrow } 12 ⟶ {\displaystyle \longrightarrow } Νν Pronunciation (UK) IPA (key): /muː/ or /mjuː/ (US) IPA (key): /mju/ Audio (US)(file) Noun Singular mu Plural mus (countable & uncountable) Mu is the twelfth letter of Greek. ΜμWikiwand - on Seamless Wikipedia browsing. On steroids.Remove ads