gnomon

American  

[noh-mon] / ˈnoʊ mɒn /

noun

1. the raised part of a sundial that casts the shadow; a style.

2. an early astronomical instrument consisting of a vertical shaft, column, or the like, for determining the altitude of the sun or the latitude of a position by measuring the length of its shadow cast at noon.

3. Geometry. (formerly) the part of a parallelogram that remains after a similar parallelogram has been taken away from one of its corners.

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gnomon British  

/ ˈnəʊmɒn /

noun

1. the stationary arm that projects the shadow on a sundial

2. a geometric figure remaining after a parallelogram has been removed from one corner of a larger parallelogram

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Other Word Forms

Derived Forms

• gnomonic
  adjective
• gnomonically
  adverb

Etymology

Origin of gnomon

1540–50; < Latin gnōmōn pin of a sundial < Greek gnṓmōn literally, interpreter, discerner

Example Sentences

In 1970, when he was diagnosed with cancer, Meatyard edited an eponymous photo book that was published by Gnomon Press; the prints in this exhibition are the ones he chose for that volume.

From The Wall Street Journal • Feb. 21, 2026

As Gnomon mania spreads across the heartland, Jimmerson breaks ground on the society’s lavish limestone temple in Burnett, Indiana, “the most fashionable suburb of Gary.”

From Slate • Dec. 31, 2020

Science fiction Gnomon by Nick Harkaway A mind-bending, many storied epic about artificial intelligence and the surveillance state.

From The Guardian • Jul. 9, 2018

For the fourth, we grow privy to the thoughts of a far-future hive-mind called Gnomon, who seems able to travel in time.

From Washington Post • Jan. 10, 2018

A translation by Charlton T. Lewis of Bengel's "Gnomon of the New Testament" was reprinted in London as the work of "two clergymen of the Church of England."

From International Copyright Considered in some of its Relations to Ethics and Political Economy by Putnam, George Haven