Definition of "scalper"

scalper

noun
plural scalpers
1. One who scalps, or removes the scalp of another.
  Quotations
  Denouncing representations of hostile Indians as vicious scalpers of innocent settlers […]
  2013, M. Elise Marubbio, Eric L. Buffalohead, Native Americans on Film: Conversations, Teaching, and Theory
2. (US, Canada) One who scalps tickets to popular entertainment events: buying them in advance and then selling them (e.g. online or just outside the venue of the event), often at inflated prices.
  Quotations
  Although 4.1 million tickets were sold for the 2023 shows—including over 2 million on the first day, a new record—scalpers jacked up prices on the secondary market to more than $22,000.
  2023 December 6, Sam Lansky, “Person of Year 2023 : Taylor Swift”, in Time‎
3. (by extension) One who scalps any other item with limited availability.
4. (gambling) A gambler who scalps.
  Quotations
  The only sure thing about scalping the Series today is that the scalper is paying the bookie a greater profit because he is making a greater number of bets.
  1961, John Scarne, Complete Guide to Gambling, page 102
5. (finance) A person on an open outcry exchange trading floor who buys and sells rapidly for his or her own account, aiming to buy from a seller and a little later sell to a buyer, making a small profit from the difference (roughly the amount of the bid/offer spread, or less).
6. A machine for removing the ends of grain, such as wheat or rye, or for separating the different grades of broken wheat, semolina, etc.
7. A surgical instrument for scraping carious bones.