Pronunciation: (bī'gôn", -gon"), [key]
past; gone by; earlier; former: The faded photograph brought memories of bygone days.
1. Usually, bygones. that which is past: Let's not talk of bygones.
2. let bygones be bygones, to decide to forget past disagreements; become reconciled: Let's let bygones be bygones and be friends again.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.