unfathomable

American  

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

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.

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unfathomable British  

/ ʌnˈfæðəməbəl /

adjective

1. incapable of being fathomed; immeasurable

2. incomprehensible

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Other Word Forms

• unfathomableness noun
• unfathomably adverb

Etymology

Origin of unfathomable

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

Example Sentences

It seems unfathomable that the German will not want to upholster his defence and attack, too, though.

From BBC

As attendance continues to decline from what it was years ago, many battle with the unfathomable idea that the track may soon close or be sold.

From Los Angeles Times

Each species on Earth can trace its roots back to the same cluster of ancestral organisms and occupies a distinct position on a single, complex, prolifically branching, unfathomably extensive and largely invisible tree of life.

From The Wall Street Journal

As the year went on, Mark Zuckerberg began a recruiting blitz that roiled the industry, offering elite researchers unfathomably large sums of money to join his AI dream team inside Meta.

From The Wall Street Journal

“I had people tell me, ‘My fundraiser represents an unfathomable amount of love,’ ” he said.

From Los Angeles Times

Related Words

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