interjection. hello, hi (especially US), howdy (US).
interjection. bye, goodbye.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
n. an acknowledgment that can be used to say hello or goodbye (aloha is Hawaiian and ciao is Italian)
Word Usage
"I suppose I could say "ciao" - which does have a certain etymological background of coming from the Italian schiavo, which means "I am your slave," and I don't much want to say that either..."