undetectable

Definitions of undetectable
  1. adjective
    not easily seen
    Synonyms:
    invisible, unseeable
    impossible or nearly impossible to see; imperceptible by the eye
  2. adjective
    barely able to be perceived
    synonyms: indiscernible, insensible
    imperceptible, unperceivable
    impossible or difficult to perceive by the mind or senses
Word Family