unfathomable

[ uhn-fath-uh-muh-buh l ]
/ ʌnˈfæð ə mə bəl /

adjective

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.

OTHER WORDS FROM unfathomable

un·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

unfathomable
/ (ʌnˈfæðəməbəl) /

adjective

incapable of being fathomed; immeasurable
incomprehensible

Derived forms of unfathomable

unfathomableness, 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