[1] : The Collaborative International Dictionary of English v.0.48

unfathomable \unfathomable\
   see fathomable.
see also:
fathomable 

[2] : WordNet (r) 2.0

unfathomable
     adj 1: of depth; not capable of being sounded or measured ant: fathomable
     2: so deep as to be unmeasurable; "the abyssal depths of the
        ocean" syn: abysmal, abyssal
     3: impossible to come to understand
see also:
fathomable abysmal abyssal 

[3] : Moby Thesaurus II by Grady Ward, 1.0

71 moby thesaurus words for "unfathomable":
   greek to one, abysmal, abyssal, all-comprehensive, all-inclusive,
   ambiguous, beyond understanding, bottomless, boundless, cavernous,
   countless, deep as hell, endless, eternal, exhaustless,
   extending everywhere, fathomless, gaping, illimitable, illimited,
   immeasurable, immense, impenetrable, inarticulate, incalculable,
   incognizable, incoherent, incomprehensible, inexhaustible,
   infinite, infinitely continuous, innumerable, inscrutable,
   interminable, interminate, limitless, measureless, no end of,
   numinous, past comprehension, perpetual, plumbless, plunging,
   rambling, shoreless, soundless, sumless, termless, unbounded,
   uncircumscribed, unconnected, unfathomed, ungraspable,
   unintelligible, universal, unknowable, unlimited, unmeasurable,
   unmeasured, unnumbered, unplumbed, unsearchable, unsounded, untold,
   without bottom, without bound, without end, without limit,
   without measure, without number, yawning

Unfathomable >> U Words
Unfathomable, definition of term: Unfathomable
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