Synonyms of unfathomable in English:

unfathomable


See US English definition of unfathomable

See UK English definition of unfathomable

See Spanish definition of insondable

adjective

1‘the dark unfathomable eyes of a stranger’

SYNONYMS
inscrutable, incomprehensible, enigmatic, incalculable, indecipherable, obscure, esoteric, abstruse, puzzling, cryptic, mysterious, mystifying, baffling, deep, profound, secretive
ANTONYMS

comprehensible, penetrable

2‘a pool of dark, unfathomable water’

SYNONYMS
deep, immeasurable, fathomless, unfathomed, unplumbed, unplumbable, bottomless, unsounded, profound
ANTONYMS

shallow