rottenly vs terribly

rottenly and terribly both are adverbs.

Word	Noun	Adjective	Verb	Adverb
rottenly	No	No	No	Yes
terribly	No	No	No	Yes

As adverbs, rottenly and terribly are synonyms defined as:

Other synonyms of rottenly include abominably, abysmally, atrociously, awfully.

rottenly (adverb)	terribly (adverb)
in a terrible manner	used as intensifiers
	in a terrible manner