Pylon

n.
  1. A tower, commonly of steelwork, for supporting either end of a wire, as for a telegraph line, over a long span.
    1. A low tower, having a truncated pyramidal form, and flanking an ancient Egyptian gateway.
    2. An Egyptian gateway to a large building (with or without flanking towers).
    3. Formerly, a starting derrick (the use of which is now abandoned) for an aeroplane.
    4. A post, tower, or the like, as on an aerodrome, or flying ground, serving to bound or mark a prescribed course of flight.