ETYM Latin obeliscus, Greek obelos a pointed pillar: cf. French obélisque.
A stone pillar having a rectangular cross section tapering towards a pyramidal top.
Tapering rectangular stone pillar.
Tall, tapering column of stone, much used in ancient Egyptian and Roman architecture. Examples are Cleopatra's Needles 1475 bc, one of which is in London, another in New York.