from The American Heritage® Dictionary of the English Language, 4th Edition
- interj. Used to express farewell.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- interj. Goodbye till we meet again.
from the GNU version of the Collaborative International Dictionary of English
- Good-by until we meet again.
from The Century Dictionary and Cyclopedia
- n. Until we meet again; good-by for the present.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a farewell remark
French : au, till the + revoir, seeing again.(American Heritage® Dictionary of the English Language, Fourth Edition)
From French with relatively formal but otherwise identical meaning, possibly due to the cumbersome nature of formal English equivalents. (Wiktionary)