gripper

noun

1. A person who or thing which grips something.

   “In a method for guiding a thread onto an empty reel after a first reel in a continuously operating spooler has become full, utilizing a moving finger on the spooler in cooperation with a gripper rotating with the empty reel […]”

2. A cover on a handle that makes it easier to grip.
3. A rubber or other material attached to a curling shoe to improve traction on the ice.
4. (slang)A ticket collector.
5. A visual component on a window etc. enabling it to be resized and/or moved.

   “To move the options bar from its default location at the top of the screen to a new location, click the gripper on the option bar's left edge and drag it to its new location.”

6. (plural-normally, slang)A foot.

   “Put those grippers away!”