轮轴

wheel and axle (mechanism) / axle

wheel / disk / ring / steamship / to take turns / to rotate / by turn / classifier for big round objects: disk, or recurring events: round, turn

wheel; disk; ring / steamship / to take turns; to rotate / classifier for big round objects: disk, or recurring events: round, turn

axis / axle / spool (for thread) / roller (for scrolls) / classifier for calligraphy rolls etc

see 壓軸戲|压轴戏[ya1 zhou4 xi4] / Taiwan pr. [zhou2]

camshaft

turboshaft