terrifically vs superbly

terrifically and superbly both are adverbs.

Word	Noun	Adjective	Verb	Adverb
terrifically	No	No	No	Yes
superbly	No	No	No	Yes

As adverbs, terrifically and superbly are synonyms defined as:

Other synonyms of terrifically include marvellously, marvelously, toppingly, wonderfully, wondrous, wondrously.

terrifically (adverb)	superbly (adverb)
(used as an intensifier) excellently	(used as an intensifier) excellently