scalper

1. (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.Examples: "We could see three different scalpers moving through the crowd outside the arena, each muttering the characteristic refrain: “Need any tickets?”"; "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."Synonyms: ticket toutCanadaUS

2. (by extension) One who scalps any other item with limited availability.broadly

3. (gambling) A gambler who scalps.Examples: "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."

4. (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).