diameter

Definition

The diameter is the longest line that you can draw across a circle. It goes through the centre of the circle and connects two points on the edge of the circle.

How can the word be used?

The diameter of a circle is the distance across the circle, passing through the centre.

Different forms of the word

Noun: diameter.

Adjective: diametrical.

Adverb: diametrically.

Synonym: breadth.

Antonym: radius.

Etymology

The word "diameter" comes from the Greek word diametros, which means "across" or "through the middle". It was first used in English in the 14th century to refer to the distance across a circle.

Question

What is the diameter of a circle?