unfathomable

  • (a) of depth; not capable of being sounded or measured
  • (s) resembling an abyss in depth; so deep as to be unmeasurable
    • the abyssal depths of the ocean
    abysmal, abyssal,
  • (s) impossible to come to understand

Synonyms

abysmal abyssal

Antonyms

fathomable plumbable soundable

See also

deep

Words of close approximity