Definition

A tool or object that casts a shadow to indicate time, often found in sundials, or a geometric shape left after removing a part from a larger shape.

Example

The gnomon of the sundial showed that it was almost noon.

Conversation

Have you ever seen a gnomon in a park?

Yeah, I think it's that tall piece that casts a shadow, right?

Exactly! It's part of a sundial and tells the time by the shadow it makes.

That’s pretty cool! I never realized how much thought goes into those designs.

Synonyms & Antonyms

Root Explanation

Gnomon → It originates from the Greek word "gnomon" (γνώμων), meaning one that knows or interpreter. In geometry, it refers to the part of a sundial that casts a shadow, thus indicating time, as it 'knows' the position of the sun.

Memory Tip

Think of the Greek word for 'one that knows' — the gnomon is the part of a sundial that 'knows' the time by casting a shadow.

Visually Confused Words