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Definition of unfathomably

unfathomably

/ʌnˈfæð.ə.mə.bli/
un · fath · om · a · bly
Adjective:unfathomable
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unfathomably Lexical Profile

unfathomably Game Scores & Validity

• adverb

1

In a manner or to a degree that is impossible to comprehend, explain, or fully grasp.

Example

"The ancient manuscript contained an unfathomably complex system of astronomical calculations."

2

To an immeasurable or unimaginably great extent or depth.

Example

"The submarine descended into an unfathomably deep trench in the Pacific Ocean."

Synonyms
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Antonyms
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• Nearby Words

unfasten
unfatherly
unfathomable
unfathomably
unfathomed
unfavorable
unfavorably

Word Origin & Etymology

Derived from the adjective 'unfathomable', which comes from Old English 'fæþm' meaning 'outstretched arms'—originally used as a unit of measurement equal to six feet for gauging the depth of water.

Usage Trend

Historical frequency of usage in published text.

180019102020
Data source: Google Books Ngram Viewer

Cite this Entry

Wordmom. (2026). Definition of Unfathomably. In Wordmom Dictionary. Retrieved Nov 3, 2026, from https://wordmom.com/dictionary/unfathomably
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