腐(くさ)るto rot, to go bad, to decay, to spoil, to fester, to decompose, to turn sour (e.g. milk), to corrode, to weather, to crumble, to become useless, to blunt, to weaken (from lack of practice), to become depraved, to be degenerate, to be morally bankrupt, to be corrupt, to be depressed, to be dispirited, to feel discouraged, to feel down, indicates scorn or disdain for another's action, to lose a bet, to be drenched, to become sopping wet