i Register
In some senses, good-by is marked as dated. Watch for register when choosing this word.
intj
Dated form of goodbye.
“Good-by, then,” said Phœbe, frankly. “I do not mean to be angry a great while, and should be sorry to have you think so. There has Cousin Hepzibah been standing in the shadow of the door-way, this quarter of an hour past! She thinks I stay too long in the damp garden. So, good-night, and good-by!”
noun
Dated form of goodbye.
Our daughter Lynda had been flying all night from California on the "Red Eye Special." She had just said good-by to her husband, Chuck, who was leaving for duty in Vietnam.