As adverbs the difference between ineffably and unknowably
is that ineffably is intensifies an adjective to mean indescribably while unknowably is in an unknowable way; ineffably.
ineffably
English
Adverb
(
en adverb)
Intensifies an adjective to mean indescribably.
- His songs are ineffably sweet and touching.
Intensifies an adjective to mean unmentionably.
- The name of God is ineffably holy.