球 'ball-game' +
馆 'public building/hall' — generic word for any indoor ball-sports arena. Specialized terms:
篮球馆 (lánqiúguǎn) basketball arena,
网球馆 (wǎngqiúguǎn) tennis center,
体育馆 (tǐyùguǎn) gymnasium. The signature NBA-style large arena is usually
球馆 in Chinese sports media.