adjective
-
incapable of being fathomed; immeasurable
-
incomprehensible
Other Word Forms
Etymology
Origin of unfathomable
First recorded in 1610–20; un- 1 ( def. ) + fathom ( def. ) + -able ( def. )
Explanation
Unfathomable means impossible to ever understand. For most people, the field of quantum mechanics is unfathomable. Fathoms are seafaring units of measure equaling about six feet. So something that is unfathomable is also immeasurable, especially when it comes to depth. If your sonar isn't bouncing anything back to you, you're dealing with an unfathomable distance. Metaphorically, unfathomable can refer to something that resembles an abyss, some figurative notion that's so deep you can't even measure it.
Vocabulary lists containing unfathomable
The Outsiders
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"To Kill a Mockingbird" by Harper Lee, Chapters 7–11
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"The Black Cat" by Edgar Allan Poe
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
I have recently been reading an extraordinary book about the rise of Hitler, "The Unfathomable Ascent: How Hitler Came to Power."
From Salon • Sep. 26, 2020
"Unfathomable" means a space for bodies where the number of bodies is no longer countable by usual means.
From Salon • Jun. 20, 2020
Unfathomable as that may seem, Pittsburgh’s playoff odds, currently at 68 percent, crash to 48 percent with a loss, and its division title odds fall to 45 percent.
From New York Times • Dec. 11, 2018
A better title for the article would have been "In Boulder, Where Unfathomable Wealth Meets Unthinkable Superficiality" Totally pointless article that hits on all the clichés of Boulder history and ignores all the downsides.
From New York Times • Aug. 31, 2016
Unfathomable, all the minutes Mabel and I will need to fill.
From "We Are Okay" by Nina LaCour
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
