bye-bye

• by-by (rare)
• bye bye
• buh-bye (eye dialect)

Reduplication of bye.

• IPA^(key): /baɪˈbaɪ/, /ˈbaɪbaɪ/, /bəˈbaɪ/

• Audio (US):

  (file)

• Rhymes: -aɪ, -aɪbaɪ

bye-bye

1. (informal, often childish) Goodbye.
   • 1995, HAL Laboratory, EarthBound, Nintendo, Super Nintendo Entertainment System:

     Bye bye! Let's play again some time!

bye-bye (plural bye-byes)

1. (colloquial, often childish) A goodbye.
2. (colloquial, childish) Bedtime for a toddler, going to sleep, going to bed.

   Synonym: beddy-bye

   Brush your teeth, it's time to go bye-bye.

   • 1885, Richard F. Burton, chapter XXII, in The Book of the Thousand Nights and a Night, volume I, The Burton Club, page 224:

     "[H]e came to the gate of the city; and finding it shut lay him down and went to by-by!"