repuesto
/reˈpwesto/ · B2 · noun · m
spare part
🔧 re- (again) + puesto (put) = something put in again to replace a part
Repuesto comes from reponer, 're- again' + 'poner to put', with puesto as the past participle of poner. A repuesto is a part you put back in place of a broken one, so it is a spare part or a spare.