diameter
deye-A-mih-tuh
Diameter (noun) means a straight line passing through the center of a circle, connecting two points on its edge; also, the length of that line. Example: “Measure the diameter of the wheel before you order a new tyre.”
noun
1
A straight line passing through the center of a circle, connecting two points on its edge; also, the length of that line.
"Measure the diameter of the wheel before you order a new tyre."
"The pipe has a diameter of about ten centimeters."
"The planet's diameter is roughly four times that of Earth's moon."
How to use diameter
Learner’s notesIn plain EnglishThe distance straight across a circle, through its middle — twice the radius.
Common pairings
measure the diameter
a diameter of
inner diameter
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Word forms
- Plural
- diameters
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Measure the _____ of the wheel before you order a new tyre.
Etymology
From Greek diametros ("line measuring across"), from dia- ("across") + metron ("measure").
Synonyms
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Rhymes for diameter
See all rhymes for diameter →Frequently asked questions
What does “diameter” mean?
The word “diameter” means a straight line passing through the center of a circle, connecting two points on its edge; also, the length of that line. In plain terms, the distance straight across a circle, through its middle — twice the radius.
How do you pronounce “diameter”?
“Diameter” is pronounced deye-A-mih-tuh (/daɪˈæmɪdɚ/ in IPA).
How do you use “diameter” in a sentence?
Here is “diameter” used in a sentence: “The pipe has a diameter of about ten centimeters.”
What part of speech is “diameter”?
“Diameter” is a noun.
Where does the word “diameter” come from?
The word “diameter” comes from Greek. From Greek diametros ("line measuring across"), from dia- ("across") + metron ("measure").
Is “diameter” a common word?
“Diameter” is a fairly common word in modern English, usually learned at around the B1 level.
What is the difference between diameter and radius?
The diameter is a straight line that passes through the centre of a circle and connects two points on its edge, while the radius runs from the centre to just one point on the edge. The diameter is always exactly twice the length of the radius, so a circle with a radius of 5 cm has a diameter of 10 cm.
What is the difference between diameter and circumference?
The diameter is the straight-line distance across a circle through its centre, whereas the circumference is the distance all the way around the circle's edge. The two are linked by pi: circumference equals diameter multiplied by pi (about 3.14159).
How do you calculate the diameter of a circle?
If you know the radius, double it: diameter = 2 x radius. If you know the circumference instead, divide it by pi (about 3.14159) to get the diameter.
Is it correct to say a measurement is 'in diameter'?
Yes. Placing 'in diameter' after a measurement is the standard way to describe circular size, as in 'the pipe is five centimetres in diameter'. An equally correct alternative is 'the pipe has a diameter of five centimetres'.
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