资料来源 : pyDict

难测的,深不可测的,无底的

资料来源 : WordNet®

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