Noun

(en noun)

A gateway to the inner part of an Ancient Egyptian temple.

A tower-like structure, usually one of a series, used to support high-voltage electricity cables.

* {{quote-book, year=1963, author=(Margery Allingham), title=(The China Governess)

, chapter=7 citation , passage=The highway to the East Coast which ran through the borough of Ebbfield had always been a main road and even now, despite the vast garages, the pylons and the gaily painted factory glasshouses which had sprung up beside it, there still remained an occasional trace of past cultures.}}

(aviation)  A structure used to mount engines, missiles etc., to the underside of an aircraft wing or fuselage.

An obelisk.

* {{quote-magazine, date=2012-01

, author= , title=The Washington Monument , volume=100, issue=1, page=16 , magazine= citation , passage=The Washington Monument is often described as an obelisk, and sometimes even as a “true obelisk,” even though it is not. A true obelisk is a monolith, a pylon formed out of a single piece of stone.}}

A traffic cone.

(American football)  An orange marker designating one of the four corners of the end zone in American football.

Noun

(en noun)

(engineering) An enclosure, from which water can be expelled, in order to give access to underwater areas for engineering works etc.

* 2003 , (Bill Bryson), A Short History of Nearly Everything , BCA, p. 213:

Caissons were enclosed dry chambers built on river beds to facilitate the construction of bridge piers.

The gate across the entrance to a dry dock.

(nautical) A floating tank that can be submerged, attached to an underwater object and then pumped out to lift the object by buoyancy; a camel.

(military) A two-wheeled, horse-drawn military vehicle used to carry ammunition (and a coffin at funerals).

(military) A large box to hold ammunition.

(military) A chest filled with explosive materials, used like a mine.

(architecture) A coffer.