slider

Meanings

1. Agent noun of slide: that which slides.
2. A potentiometer with a linearly sliding control.
3. A widget allowing the user to select a value or position on a sliding scale.
4. A sliding door.
5. A pitch thrown with added pressure by middle and ring fingers yielding a combination of backspin and sidespin, resulting in a motion to the left when thrown by a right handed pitcher.
6. A similar delivery in which the wrist and ring finger work to impart backspin to the ball.
7. A small sandwich, typically served in a warm bun.
8. The movable part of a zip fastener that opens or closes the row of teeth.
9. A rectangle of fabric that helps produce an orderly parachute deployment.
10. Synonym of slide (“child's play equipment”).
11. A piece of Teflon or similar material attached to a curling shoe that allows the player to slide along the ice.
12. An open-toed and backless sandal; a slide.

1. A surname.

Etymology

From slide + -er. The meaning "small hamburger" was originally used to describe onion-steamed small burgers at White Castle restaurants, formerly spelt "Slyder". Regarding the senses about control devices or widgets: physical sliders (potentiometers serving as rheostats) predate virtual ones (elements in graphical user interfaces), and the virtual ones are so named because their concept is the abstraction of the physical ones; if more explanation on that topic is needed, it is available in the Wikipedia articles on skeuomorphs, icons, and the desktop metaphor.