George Clooney's Wife -- Back to Work ... On Important World Stuff (PHOTO)

George Clooney's wife (sounds weird, right?) jumped back on the lawyer beat Tuesday ... heading out to a big international lawyer meeting -- where it's a safe bet she'll have the best legs in the room.

Amal Clooney -- yes, she's now listed under her married name on the firm's website -- is helping Greece convince Great Britain to return the Elgin Marbles ... a collection of ancient sculptures that were originally part of the Parthenon.