believably vs probably

believably and probably both are adverbs.

Word	Noun	Adjective	Verb	Adverb
believably	No	No	No	Yes
probably	No	No	No	Yes

As adverbs, believably and probably are synonyms defined as:

believably and probably: easy to believe on the basis of available evidence

Other synonyms of believably include credibly, plausibly.

believably (adverb)	probably (adverb)
in a believable manner	with considerable certainty; without much doubt
easy to believe on the basis of available evidence	easy to believe on the basis of available evidence