Definition of "ineffable" []

• Incapable of being expressed; indescribable or unutterable. See Synonyms at unspeakable. (adjective)
• Not to be uttered; taboo: the ineffable name of God. (adjective)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "It is a fond conceit of the superstitious Jews that his blasphemy was in pronouncing the name of Jehovah, which they call ineffable: he that made himself known by that name never forbade the calling of him by that name."
• "Something about the plastic face, a face frozen in an expression of ineffable sadness."
• "You may give them all they need of food and drink and make the conditions of their existence as favorable as possible, and they may grow and bloom, but there is a certain ineffable something that will be missing if you do not love them, a delicate glory too spiritual to be caught and put into words."