lousy vs rotten

lousy and rotten both are adjectives.

Word	Noun	Adjective	Verb	Adverb
lousy	No	Yes	No	No
rotten	No	Yes	No	No

As adjectives, lousy and rotten are synonyms defined as:

Other synonyms of lousy include crappy, icky, shitty, stinking, stinky.

lousy (adjective)	rotten (adjective)
very bad	having decayed or disintegrated; usually implies foulness
infested with lice	damaged by decay; hence unsound and useless
vile; despicable	very bad