(1) An isolated black hole is, of course, undetectable , except by its gravitational pull - the way it distorts space in its vicinity.(2) Then, slightly with a barely undetectable motion, she ran her fingertips across his neck.(3) His eyes met mine in the rearview mirror… and lingered there, casting me a small undetectable smile.(4) And there's another sound, too: a low, whispering rumble, almost undetectable .(5) The extra risk of developing cancer from low doses of ionising radiation is so small that it is undetectable in the population.(6) Rootkits are the ultimate backdoor, giving hackers ongoing and virtually undetectable access to the systems they exploit.(7) The company claims this process takes just microseconds, making lag undetectable .(8) Harmless and humane, the cats simply don't like the sound, which is undetectable to the human ear.(9) In four months of observation, this orbital movement would be so slight as to be undetectable from Earth.(10) ‘You could have fraud on a scale never seen before, and it will be completely undetectable ,’ he said.(11) Further, if they are undetectable by their taste, smell, or colour their attractiveness as poisons is enhanced.(12) Both believed they were using an undetectable drug and would never be caught.(13) He didn't hear what the soldier said, it was in a low whisper that was undetectable from his position in the room.(14) He shrugged, and his eyes glimmered slightly with an undetectable sadness.(15) It can often be dissolved in a drink and is undetectable .(16) I was beginning to get a little carsick, when we stopped with a slightly, almost undetectable , jerk.