godan verb (-su), transitive verb
let spoil; leave to rot; cause to rot; corrode
Transitive verb meaning to cause something to rot, spoil, or corrode, often through neglect or improper storage.
湿気の多い場所に置くと、食べ物を腐らすことがある。
Leaving food in a humid place can cause it to spoil.
Acid corrodes metal.
godan verb (-su), transitive verb
Figurative use: to dampen someone's spirits or enthusiasm. Often used in the expression 気を腐らす.
彼の一言が彼女の気を腐らせた。
His single remark disheartened her.