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unfathomable

unfathomable

23 8.6
Very hard to understand or measure how deep something is
  • adjective
  • /ʌnˈfæðəməbl/
translation icon : incomprensible
  • The depths of the ocean are unfathomable, hiding secrets we may never uncover.
  • an unfathomable mystery
  • unfathomable love
  • unfathomable power

On top of all this, we have the almost unfathomable costs of two world wars.

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Examples

  • Her reasons for leaving the company were unfathomable to her colleagues.

  • At issue now is similarly insidious and unfathomable destruction, the congressional budget cuts aimed largely at poor people.

    Academic text (1995)
  • Losing a mother, it's an unfathomable loss.

  • You are unfathomable to me.

  • On top of all this, we have the almost unfathomable costs of two world wars.

  • You have been blessed with unfathomable power.

  • But all of those stars were surrounded by unfathomable, empty loneliness.

  • It's an unfathomable twist of fate when God takes someone so young and innocent.

  • For many in the mainstream, this approach to life may seem unfathomable and senseless.

    Academic text (2013)
  • And as we mourn the loss of this beloved wife, mother and friend, it only makes her choice that much more unfathomable.

Synonyms

unintelligible
vsunfathomable
8.6

Not clear enough to understand

also includes very deep or profound cases beyond mere lack of clarity
deep
vsunfathomable
583 7.6

Hard to understand or explain

is stronger, sometimes meaning totally impossible to understand rather than just complex
mysterious
vsunfathomable
498 5.1

Hard to understand or explain because it seems strange

can also stress extreme depth or total unknowability beyond mere obscurity
inexplicable
vsunfathomable
47 7.8

Hard to explain or understand

is broader, also covering cases that are deeply profound rather than only unexplained
incomprehensible
vsunfathomable
46 8.8

Difficult or impossible to understand

also covers things that are very deep rather than only unclear
inconceivable
vsunfathomable
46 7.4

Impossible to imagine or believe

is different when referring to great depth or plain incomprehension rather than impossibility
mind-boggling
vsunfathomable
  • Informal
31 7.0

Very surprising or hard to understand

often also refers to things so deep they resist any simple grasping
enigmatic
vsunfathomable
27 8.1

Hard to understand and often seems mysterious

can also mean extremely deep or unknowable rather than simply puzzling
baffling
vsunfathomable
27 6.4

Hard to understand and causing confusion

may refer instead to things so deep they defy ordinary understanding
indescribable
vsunfathomable
21 5.4

So wonderful or strange that words cannot show it

focuses more on absolute inability to understand rather than only being hard to describe
unexplainable
vsunfathomable
19 7.0

Something people cannot understand or find a clear reason for

also includes very deep or profound examples beyond lacking explanation
unknowable
vsunfathomable
19 7.4

Something you cannot find out or understand

is similar but also highlights great depth rather than only unknowability
impenetrable
vsunfathomable
14 8.3

Very hard to understand

also covers great depth or size in a nonliteral sense sometimes
inscrutable
vsunfathomable
12 8.9

Hard to understand because it shows no clear meaning or feeling

often stresses extreme depth or unknowability rather than only puzzlement
ineffable
vsunfathomable
  • Formal
8 9.5

So great that words cannot describe it

focuses on being impossible to understand rather than only beyond expression
indefinable
vsunfathomable
4 6.9

Hard to describe or explain in words

often refers instead to inability to mentally grasp rather than only definition issues
inexpressible
vsunfathomable
3 7.5

A feeling so strong that you cannot describe it in words

is about not being understood at all, not only failing to be expressed
undefinable
vsunfathomable
3 6.8

Hard to describe exactly in words

is used more for pure incomprehension rather than only vague boundaries
fathomless
vsunfathomable
2 8.6

So deep that you cannot measure or understand it

can also mean purely impossible to understand without physical depth being present
abysmal
vsunfathomable
1 6.8

Very deep like a dark hole with no bottom

can instead refer to things that cannot be understood or are baffling
ungraspable
vsunfathomable
1 8.6

Difficult to understand even after thinking about it

sometimes adds idea of extreme depth rather than only lack of comprehension
uninterpretable
vsunfathomable
1 8.2

Not possible to understand or explain

can also mean very deep or mysterious beyond mere unclear meaning
enigmatical
vsunfathomable
1 9.3

Hard to understand, like a puzzle

is often used for very deep, hard to fully comprehend situations
boggling
vsunfathomable
1 7.5

Very surprising and hard to understand because it is unusual

can apply to very deep or vast matters beyond mere surprise or wonder
unfathomed
vsunfathomable
1 9.9

Too deep or mysterious to understand

is used more for mental inability to understand rather than physical depth
abyssal
vsunfathomable
1 9.8

Very deep and hard to understand or imagine

is broader and also applies to mental or intellectual inability to understand
unnamable
vsunfathomable
1 7.7

Too hard to describe in words

is more about being impossible to mentally understand than lacking a name
unsearchable
vsunfathomable
1 7.6

Hard to know what someone thinks or feels

is broader, also applying to vast depth beyond private, unreadable inner states
uncomprehensible
vsunfathomable
  • Informal
9.9

Very hard to understand

is the standard term and also includes very deep sense at times
inapprehensible
vsunfathomable
9.9

Hard to understand or explain

also implies great depth or complexity beyond just being hard to grasp
incognoscible
vsunfathomable
  • Archaic
9.9

Not possible for people to know or understand

stresses depth or profoundness as well as lack of understanding
unperceivable
vsunfathomable
9.1

Too small, slow, or quiet for people to notice

also applies to things that are deeply complex rather than merely unseen

Antonyms

1 4.9

Easy to understand

fathomable
  • Specialized
6.9

Can be measured to find how deep water is

Compounds

A thing that people cannot understand or explain

Very deep sadness that feels too strong to understand

How Incomprehensible

unfathomable
23 8.6
mysterious
498 5.1
baffling
27 6.4
puzzling
42 4.6

Surface Forms

unfathomable positive

Morphology

unfathomable = fathomable (transparent) = un + fathom + able

The adjective is formed by prefixing 'un-' to 'fathomable' (fathom + -able), producing a straightforward negation.

Etymology

Unfathomable comes from the word fathom, which meant 'to measure depth' in the sea, and the prefix un- means 'not'. So something unfathomable is 'not measurable' — it feels too deep or too hard to understand.