[interjection bahy-bahy; noun, adverb bahy-bahy]
Baby Talk. sleep.
- to leave; depart; go out.
- to go to sleep; go to bed.
go bye-bye, Baby Talk.
Origin of bye-bye
1700–10; apparently orig. nursery phrase used to lull a child to sleep, later construed as reduplicative form of bye, short for goodbye
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019