unfathomable
UK /(ˌ)ʌnˈfæðəməbl̩/ · US /ˌʌnˈfæð(ə)məb(ə)l/ adjective
- adjective Especially of depth: physically incapable of being measured; immeasurable.
- adjective (figurative) Impossible to grasp the extent of, or to fully know or understand. “The sheer number of warriors the enemy attacked with was unfathomable.”
Synonyms
abyssal incalculable inestimable soundless unplumbable unsoundable bottomless fathomless impenetrable unintelligible abstruse Chinese dense enigmatic Greek inapprehensible incognizable incomprehensible ineffable inenubilable abysmal
Antonyms
calculable estimable fathomable measurable plumbable soundable explicable intelligible penetrable understandable apprehensible clear
Etymology
From un- (prefix meaning ‘not’) + fathom (“to measure the depth of (water); (figurative) to deeply understand (someone or something)”) + -able (suffix forming adjectives denoting things not able or fit to be done).
Sources: Wiktionary · WordNet 3.0 — from the Wiktionary entry “unfathomable”, CC BY-SA 4.0. Details