noun

• (uncountable) The attribute or characteristic of acting in secrecy, or in such a way that the actions are unnoticed or difficult to detect by others.
• (archaic, countable) An act of secrecy, especially one involving thievery.
  "Claudio.[...] But it chances The stealth of our most mutuall entertainment With Character too grosse, is writ on Iuliet."

verb

• (especially military, computing) To conceal or infiltrate through the use of stealth.
• (slang, transitive) To subject (someone) to stealthing (sexual intercourse without a condom through deception, for example removing the condom mid-act).
  "For her, there's a clear link between this behavior and that of avowed stealthers: : both stem from a place of sexism and misogyny, and to the extent that they differ, it's only by degree. Tellingly, Davis's work treats deception as merely one of several ways that men engage in the behavior she terms "condom use resistance." […] To the best of my knowledge, I've never been stealthed."

adj

• (military, aviation, vehicles, technology) Having properties that diminish radar signatures.
• (transgender) Hiding one's transgender status (in general or in specific areas of one's life, e.g. at work) after transition.
  "go stealth; be stealth; live stealth"