setscrew

1. A screw, often without a head, used to hold two parts together.
2. A screw used to regulate the tension of a spring.

1. A screw used to fix a collar, knob, or other detachable part to a shaft or part of a machine; also called a grub screw.
2. A screw in a cramp that brings the two sides in close contact.

setscrews, 1