ETYM Latin ineffabilis: cf. French ineffable. Related to In- not, and Effable, Fame.
Too sacred to be uttered; SYN. unnameable, unspeakable, unutterable.
Indescribable; unspeakable.
Defying expression; SYN. unexpressible.
1. Impossible or difficult to pronounce correctly.
2. Very difficult to pronounce correctly; SYN. unutterable.
Not utterable; incapable of being spoken or voiced; inexpressible; ineffable; unspeakable
To an inexpressible degree; SYN. indescribably, unutterably, unspeakably.
In an inexpressible manner, indescribably