undetected

verb (used with object)

1. to discover or catch (a person) in the performance of some act: to detect someone cheating.
2. to discover the existence of: to detect the odor of gas.
3. to find out the true character or activity of: to detect a spy.
4. Telecommunications.
   1. to rectify alternating signal currents in a radio receiver.
   2. to demodulate.

adjective

1. not perceived, noticed, or discoveredthe fake bomb passed undetected

verb (tr)

1. to perceive or noticeto detect a note of sarcasm
2. to discover the existence or presence of (esp something likely to elude observation)to detect alcohol in the blood
3. to extract information from (an electromagnetic wave)
4. obsolete to reveal or expose (a crime, criminal, etc)

adj.1590s, from un- (1) “not” + past participle of detect. Undetectable is recorded from 1863. v.early 15c., from Latin detectus, past participle of detegere “uncover, expose,” figuratively “discover, reveal, disclose,” from de- “un-, off” (see de-) + tegere “to cover” (see stegosaurus). Related: Detected; detecting.