(noun)
(historical) the skin at the top, sides, and back of the head, along with the hair growing out of it, taken from an enemy's head as a token/trophy of battle or victory by some Native American peoples;
e.g. The warrior took the scalp from the chief of the defeated army as a trophy.
(verb)
to remove the required or desired parts of something and get rid of the rest, for example (historical) to cut away the skin of an enemy's head with the hair attached as a trophy of battle, as done by some Native American peoples;
e.g. They decided to scalp the machine for useful parts and then leave it in the dumpster. The warrior began to scalp the fallen chief.
(verb)
(informal) to buy something and sell it at a much higher price in order to make a quick profit;
e.g. He tried to scalp the concert tickets because he knew that people would pay any price to attend.
(verb)
(informal) to subject someone to severe punishment;
e.g. She said she would scalp them if they did something like that again.