gno·mon (nōmŏn′, -mən)
1. An object, such as the style of a sundial, that projects a shadow used as an indicator.
2. The geometric figure that remains after a parallelogram has been removed from a similar but larger parallelogram with which it shares a corner.
[Latingnōmōn, fromGreek, interpreter, pointer of a sundial, fromgignōskein, to know; see gnō- in the Appendix of Indo-European roots.]
(click for a larger image)
(click for a larger image)gnomon
top: on a sundial
bottom: A gnomon of the parallelogram ABCD is the shaded figure HBCDKL.
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