gnomon

/'noumɔn/

Thân thiện

The sundial's gnomon casts a sharp shadow on the Roman numeral XII.

Definition

1. Noun:
   • The projecting piece on a sundial that casts the shadow: A "gnomon" is the part of a sundial, typically a rod or triangular plate, that stands upright and whose shadow indicates the time of day by its position on a marked dial.

Examples of Usage

• Noun:
  • The ancient sundial's bronze gnomon had weathered over centuries.
  • To tell the time, you observe where the shadow of the gnomon falls on the dial.

Advanced Usage

• In geometry: The term "gnomon" can also refer to the shape that remains when a smaller parallelogram is removed from a corner of a larger, similar one.
  • In the diagram, the L-shaped figure is the gnomon to the smaller square.

Variants and Related Words

• Gnomonic (adj): Pertaining to a gnomon or to the art of dialing (sundial construction).
  • The gnomonic projection is a map projection where great circles are shown as straight lines.

Synonyms

• Style: Another term for the gnomon of a sundial.
• Pointer: A more general term that can describe the indicating part of an instrument.

Related Idioms

Học thuật

Noun

1. indicator provided by the stationary arm whose shadow indicates the time on the sundial