good-by

1. datedDated form of goodbye.

   "It's good-by for good, Margot, good-by and good luck."

   1924 July 28 [1923 August 28], Samuel Badisch Ornitz, “Sixth Period”, in Haunch Paunch and Jowl, eighth printing, New York, N.Y.: Boni and Liveright, section I, page 265

   1 more example

   “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!”

   1851 April 9, Nathaniel Hawthorne, “Phœbe’s Good-by”, in The House of the Seven Gables, a Romance, Boston, Mass.: Ticknor, Reed, and Fields, →OCLC, page 235

plural good-bys

1. datedDated 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.

   1971, Lyndon Johnson, “A Beginning and an End: March 31, 1968”, in The Vantage Point, Holt, Reinhart & Winston, →ISBN, →LCCN, →OCLC, page 431