Verb (5-dan, る, intransitive)
1.  to rot;  to go bad;  to decay;  to spoil;  to fester;  to decompose;  to turn sour (e.g. milk)
2.  to corrode;  to weather;  to crumble
3.  to become useless;  to blunt;  to weaken (from lack of practice)
4.  to become depraved;  to be degenerate;  to be morally bankrupt;  to be corrupt
5.  to be depressed;  to be dispirited;  to feel discouraged;  to feel down
Auxiliary verb (5-dan, る)
Usually written in kana
Kansai-ben
6.  to have the audacity to;  to be bastard enough to
after the -masu stem of a verb; indicates scorn or disdain for another's action
Archaic
Verb (5-dan, る, intransitive)
7.  to lose a bet
8.  to be drenched;  to become sopping wet