Jumar vs. Jammer — What's the Difference?

A device used in ascending a fixed rope, having a springloaded cam that grips the rope when weight is applied but allows free movement upwards when the load is lifted.

To drive or wedge forcibly into a tight position

(climbing) A device, used to clip on a rope, that tightens when weight is applied, thus allowing the rope to be climbed.

To activate or apply (a brake) suddenly. Often used with on

(intransitive) To climb using this device.

To cause to become unworkable because a part is stuck

To cause (moving parts, for example) to lock into an unworkable position

To pack (items, for example) to excess; cram

To fill (a container or space) to overflowing

To block, congest, or clog

To crush or bruise

(Electronics) To interfere with or prevent the clear reception of (broadcast signals) by electronic means.

(Baseball) To throw an inside pitch to (a batter), especially to prevent the batter from hitting the ball with the thicker part of the bat.

To become wedged or stuck

To become locked or stuck in an unworkable position

To force one's way into or through a limited space

(Music) To participate in a jam session.

(Basketball) To make a dunk shot.

The act of jamming or the condition of being jammed.

A crush or congestion of people or things in a limited space

A trying situation.

See jam session.

Any device used to jam radio reception.

A form of swimwear used by athletes.

A musician who jams.

A device (e.g. a jumar) which will slide along a rope in one direction but not the other, used in rock-climbing, caving etc.

(roller derby) A player who attempts to score points by making their way past other players.

A transmitter used to broadcast electronic jamming