off-season

noun

1. a time of year other than the regular or busiest one for a specific activity: Fares are lower in the off-season.
2. a time of year when business, manufacturing activity, etc., is less than normal or at an unusually low point.

adjective

3. of, relating to, or during the off-season: off-season hotel rates.

adverb

4. in or during the off-season: Traveling off-season is the easiest way to save vacation money.

n.1848, “a period when business is down,” from off (adv.) + season (n.).