diameter

B1 Topic:Space, Position & Direction

US /daɪˈæmɪdɚ/ UK /daɪˈæmɪtə(ɹ)/ See IPA manual

Freq #15225

Meanings

1

noun
A straight line passing through the centre of a circle from one side to the other.

Draw a line through the centre to mark the diameter of the circle.
2

noun
The length of such a line; the width of a round object across its centre.

The pipe has a diameter of ten centimetres.

Thesaurus

Synonyms

1 noun · a straight line passing... diam

Word family

Forms diameters

Derived forms aerodiametercircumdiameterdiameterwisemultidiameter

Related forms circumference diametric diametrically radiussemidiameter

Appears in

Phrases (1)

See all

Etymology

From Old French diametre (French diamètre), from Latin diametros, from Ancient Greek διάμετρος (diámetros) (γραμμή (grammḗ)) (diametros grammē, “line measuring across”), from διά (diá, “across”) + μέτρον (métron, “measure”). By surface analysis, dia- + -meter.

Topics

Space, Position & Direction

External links

# diameter

**Type:** Word
**Level:** B1
**Part of speech:** noun
**IPA (US):** /daɪˈæmɪdɚ/
**IPA (UK):** /daɪˈæmɪtə(ɹ)/
**Frequency rank:** 15225

## Meanings
1. A straight line passing through the centre of a circle from one side to the other.
2. The length of such a line; the width of a round object across its centre.

## Examples
- Draw a line through the centre to mark the diameter of the circle.
- The pipe has a diameter of ten centimetres.

## Derived Forms
- aerodiameter
- circumdiameter
- diameterwise
- multidiameter

## Related Forms
- circumference
- diametric
- diametrically
- radius
- semidiameter

## Roots and Affixes
- Affix: dia- - through
- Affix: -meter - measuring device

## Etymology
From Old French diametre (French diamètre), from Latin diametros, from Ancient Greek διάμετρος (diámetros) (γραμμή (grammḗ)) (diametros grammē, “line measuring across”), from διά (diá, “across”) + μέτρον (métron, “measure”). By surface analysis, dia- + -meter.

## AI Etymology
diameter comes from Old French diametre (French diamètre), from Latin diametros, from Ancient Greek διάμετρος (diámetros) (γραμμή (grammḗ)) (diametros grammē, “line measuring across”), from διά (diá, “across”) + μέτρον (métron, “measure”). By surface analysis, dia- + -meter. Current senses include A straight line passing through the centre of a circle from one side to the other and The length of such a line; the width of a round object across its centre. English relatives and later formations include aerodiameter, circumdiameter, diameterwise, circumference, diametric.

## Topics
- Space, Position & Direction

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