Obelisk

n. tall four-sided stone pillar tapering to a pyramidal top

An obelisk (Greek ὀβελίσκος [obeliskos], diminutive of ὀβελός [obelos], "needle") is a tall, narrow, four-sided, tapering monument which ends in a pyramidal top. Ancient obelisks were made of a single piece of stone (a monolith). The term stele (plural: stelae) is generally used for other monumental standing inscribed sculpted stones not of classic obelisk form.
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Noun
1. a stone pillar having a rectangular cross section tapering towards a pyramidal top
(hypernym) column, pillar
(hyponym) Washington Monument
2. a character used in printing to indicate a cross reference or footnote
(synonym) dagger
(hypernym) character, grapheme, graphic symbol

n. obelisk, tall four-sided stone pillar tapering to a pyramidal top; Cleopatra's needle, one of two large stone obelisks which were originally erected in Egypt by Thutmose III

n. obelisk, tall four-sided stone pillar tapering to a pyramidal top