noun
between-season wear; spring/autumn clothing
Refers to clothing suitable for spring or autumn, lighter than winter wear but heavier than summer wear. Often used in contrast with 夏服 (summer clothes) and 冬服 (winter clothes).
See also: 合着
そろそろ合服を出さないと、暑くなってきた。
It's getting warmer; I should get out my between-season clothes soon.
この合服は春と秋にちょうどいい厚さだ。
This between-season wear is just the right thickness for spring and autumn.
Compound of 合 (あい, 'between') and 服 (ふく, 'clothing'), referring to clothing for the transitional seasons.