Real Dictionary

e.m.u. in British English
abbreviation for: electromagnetic unit

electromagnetic unit in British English
noun: any unit that belongs to a system of electrical cgs units in which the magnetic constant is given the value of unity and is taken as a pure number

emu
countable noun: An emu is a large Australian bird which cannot fly.

EMU in American English
any of a family (Dromaiidae) of large, flightless Australian birds
electromagnetic units
abbreviation
noun: a large, flightless, ratite bird, Emu (Dromaius) novaehollandiae, of Australia, resembling the ostrich but smaller and having a feathered head and neck and rudimentary wings

emu in British English
abbreviation for: European Monetary Union
noun: a large Australian flightless bird, Dromaius novaehollandiae, similar to the ostrich but with three-toed feet and grey or brown plumage: order Casuariiformes