Tripod /(?)/

Tri·pod

Tripod

n.
  1. Any utensil or vessel, as a stool, table, altar, caldron, etc., supported on three feet.
  2. A three-legged frame or stand, usually jointed at top, for supporting a theodolite, compass, telescope, camera, or other instrument.

Phrases & Compounds
Tripod of life
the three organs, the heart, lungs, and brain; -- so called because their united action is necessary to the maintenance of life.