Definition

A type of telescope that is used to measure small angles between celestial objects, especially to determine the size of the sun and other celestial bodies.

Example

The astronomer used a heliometer to measure the distance between the stars.

Conversation

Have you ever used a heliometer for star gazing?

No, I haven't! What does it do exactly?

It helps measure the angular distances between celestial bodies.

That sounds really cool! I’d love to try it sometime.

Synonyms & Antonyms

Root Explanation

Heliometer → It is formed from "helios" (ἥλιος) (meaning sun) and "metron" (μέτρον) (meaning measure). The word refers to an instrument used to measure the distance to the sun or the angular diameter of the sun.

Memory Tip

Think of 'helios' meaning sun and 'metron' meaning measure — a heliometer is a tool that measures something related to the sun.

Visually Confused Words