unfathomable

[uhn-fath-uh-muh-buhl]

adjective

1. not able to be fathomed, or completely understood; incomprehensible.

   heroism in the face of unfathomable conflict.

2. not able to be measured with a sounding line, or fathomed.

   unfathomable depths of the ocean.

unfathomable

/ ʌnˈfæðəməbəl /

adjective

1. incapable of being fathomed; immeasurable

2. incomprehensible

Other Word Forms

• unfathomableness noun
• unfathomably adverb

Word History and Origins

Origin of unfathomable¹

First recorded in 1610–20; un- ¹ ( def. ) + fathom ( def. ) + -able ( def. )

Related Words

• baffling 
• impenetrable 
• incomprehensible 
• indecipherable 
• inexplicable 
• unknowable