[uhn-fath-uh-muh-buh l]


not able to be fathomed, or completely understood; incomprehensible: heroism in the face of unfathomable conflict.
not able to be measured with a sounding line, or fathomed: unfathomable depths of the ocean.

Nearby words

  1. unfamiliar,
  2. unfancied,
  3. unfashionable,
  4. unfasten,
  5. unfathered,
  6. unfathomed,
  7. unfavorable,
  8. unfavourable,
  9. unfavoured,
  10. unfazed

Related formsun·fath·om·a·ble·ness, noun

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Examples from the Web for unfathomable

British Dictionary definitions for unfathomable



incapable of being fathomed; immeasurable
Derived Formsunfathomableness, noununfathomably, adverb

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Word Origin and History for unfathomable



1610s, originally in the figurative sense, of feelings, conditions, etc., from un- (1) "not" + fathomable. Literal sense attested from 1670s. Related: Unfathomably.

Online Etymology Dictionary, © 2010 Douglas Harper