- the raised part of a sundial that casts the shadow; a style.
- 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.
- Geometry. (formerly) the part of a parallelogram that remains after a similar parallelogram has been taken away from one of its corners.
Origin of gnomon
Examples from the Web for gnomon
No doubt, however, it was a sun-dial, or gnomon of some kind.The Story of Eclipses
The Gnomon is any one of the Diagonall with the two complements.
There is therefore in every Parallelogramme a double Gnomon; as in these two examples.
But I landed in the dark chamber of a Gnomon, waist-deep in loose wheat.
I mounted the only unsealed Gnomon and shouted down into its cavernous depths.
- the stationary arm that projects the shadow on a sundial
- a geometric figure remaining after a parallelogram has been removed from one corner of a larger parallelogram
Word Origin and History for gnomon
"vertical shaft that tells time by the shadow it casts" (especially the triangular plate on a sundial), 1540s, from Latin gnomon, from Greek gnomon "indicator," literally "one who discerns," from gignoskein "to come to know" (see gnostic (adj.)).