bygone

UK: /ˈbaɪgɒn/ US: /ˈbaɪˌgɔn, -ˌgɑn/ ,(bī′gôn′, -gon′)

WordReference Random House Learner's Dictionary of American English © 2025

by•gone /ˈbaɪˌgɔn, -ˌgɑn/   adj. [before a noun]

1. earlier;
   former;
   past:
   bygone days.

Idioms

2. Idioms let bygones be bygones, to put aside past disagreements:
   willing to let bygones be bygones.

WordReference Random House Unabridged Dictionary of American English © 2025

by•gone  (bī′gôn′, -gon′), adj. 

1. past;
   gone by;
   earlier;
   former:
   The faded photograph brought memories of bygone days.

n. 

2. Usually, bygones. that which is past:
   Let's not talk of bygones.
3. Idioms let bygones be bygones, to decide to forget past disagreements;
   become reconciled:
   Let's let bygones be bygones and be friends again.

• 1375–1425; late Middle English (north) by-gane; see gone, by¹

Collins Concise English Dictionary © HarperCollins Publishers::

bygone / ˈbaɪˌɡɒn/ adjective

1. (usually prenominal) past; former

noun

1. (often plural) a past occurrence
2. (often plural) an artefact, implement, etc, of former domestic or industrial use, now often collected for interest
3. let bygones be bygones ⇒ to agree to forget past quarrels