What is Bye-and-bye?
1.
This is a play on the phrase by-and-by which means: some future time or occasion.
By changing the spelling it implies that we are saying goodbye until some future time or occasion; til later on.
This is an especially useful phrase when you want to say goodbye to someone that has passed away.
Yo man, I miss you...I'll catch you in the bye-and-bye.
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