abysmally vs terribly

abysmally and terribly both are adverbs.

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

As adverbs, abysmally and terribly are synonyms defined as:

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

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