Merriam-Webster Collegiate Dictionary - pylon

 noun  Etymology: Greek pylon, from pyle gate  Date: 1850  1.  a. a usually massive gateway  b. an ancient Egyptian gateway building in a truncated pyramidal form  c. a monumental mass flanking an entranceway or an approach to a bridge  2.  a. chiefly British a tower for supporting either end of usually a number of wires over a long span  b. any of various towerlike structures  3.  a. a post or tower marking a prescribed course of flight for an airplane  b. traffic cone  c. one of the flexible upright markers positioned on a football field at the corners of the end zone  4. a rigid structure on the outside of an aircraft for supporting something (as an engine or missile) — see airplane illustration