ineffably vs unspeakably

ineffably and unspeakably both are adverbs.

Word	Noun	Adjective	Verb	Adverb
ineffably	No	No	No	Yes
unspeakably	No	No	No	Yes

As adverbs, ineffably and unspeakably are synonyms defined as:

Other synonyms of ineffably include indescribably, inexpressibly, unutterably.

ineffably (adverb)	unspeakably (adverb)
to an inexpressible degree	to an inexpressible degree