adj. 1. Incapable of being expressed; indescribable or unutterable: ineffable joy. 2. Not to be uttered; taboo: the ineffable name of God. [Middle English, from Old French, from Latin ineffābilis : in-, not; see IN-1 + effābilis, utterable (from effārī, to utter : ex-, ex- + fārī, to speak; see bhā-2 in the Appendix of Indo-European roots).] in·ef′fa·bili·ty, in·effa·ble·ness n. in·effa·bly adv. |
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