jumar

 
Pronunciation: /ˈdʒuːmə/
Climbing

noun

  • a clamp that is attached to a fixed rope and automatically tightens when weight is applied and relaxes when it is removed.

verb (jumars, jumaring, jumared)

[no object]
  • climb with the aid of a jumar: the second climber jumars up the fixed rope

Origin:

1960s: originally in Swiss use, of unknown origin