roulette

noun

1. (uncountable)A game of chance in which a small ball is made to move round rapidly on a circle divided off into numbered (usually red and black) spaces. When the ball stops, it indicates the result of a variety of wagers permitted by the game.
2. (figuratively, uncountable)An instance of risk-taking, especially when the downside exceeds the upside (contrary to the game of roulette where only the wager is lost).

   “Doctors and health officials said that the WRC-TV documentary, "DPT: Vaccine Roulette," emphasized the risks of the vaccine while ignoring the dangers of the disease, which has been almost wiped out in this country.”

   “They would all rather take their chances with the existing policy-making roulette rather than follow process discipline.”

   “By contrast giving treatments open-label slows everything down by leading us up blind alleys while playing roulette with our patients' lives.”

3. (countable)A small toothed wheel used by engravers to roll over a plate in order to produce rows of dots.
4. (countable)A similar wheel used to roughen the surface of a plate, as in making alterations in a mezzotint.
5. (countable)The locus of a point on a plane curve that rolls without slipping along another fixed plane curve.
6. (countable, uncountable)Any of the small incisions on a sheet of stamps, used as an alternative to perforations.
7. (countable, uncountable)A cylindrical curler for the hair.

verb

1. To separate or decorate by incisions made with a small toothed wheel.

   “to roulette a sheet of postage stamps”