noun
ensemble; instrumental group
Refers to a group of musicians who play instruments together, such as a chamber ensemble or orchestra. Often used in names of specific groups.
地元の合奏団がコンサートを開いた。
The local ensemble held a concert.
彼は弦楽合奏団に所属して
He belongs to a string ensemble.
合唱団 is a choir (vocal group), whereas 合奏団 is an instrumental ensemble.
Compound of 合奏 (がっそう, 'instrumental ensemble') and 団 (だん, 'group'). The reading がっそう is a regular sound change from 合 (がっ) + 奏 (そう).