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

• gnomonic adjective
• gnomonically adverb

Etymology

Origin of gnomon

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