ROFL . . . I was reading a description of one of those cup warmers on Amazon. Omigod, lol, I thought a cup warmer would be just a bit bigger than your regular coffee cup. Seems I was wrong, it’s 37″ in diameter. Now, if I do the math, the circumference would be ~116 inches. That is some BIG cup.
So, yeah, it’s obviously a word confusion circumference vs diameter.
A circumference is the length of the circle’s boundary.
The diameter is the distance from one side of the circle to the other, going through the center of the shape.
Ya never know when you’ll need to know the differences in a word confusion.
Word Confusions . . .
. . . started as my way of dealing with a professional frustration with properly spelled words that were out of context in manuscripts I was editing as well as books I was reviewing. It evolved into a sharing of information with y’all. I’m hoping you’ll share with us words that have been a bête noire for you from either end.
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| Circumference | Diameter |
|---|---|
Image from page 26 of A High-school Astronomy: In which the descriptive, physical, and practical are combined …” (1859) by Mattison, Hiram is courtesy of Internet Archive Book Images and is under the CC0 1.0 license, via Flickr. — That dark brown line? That’s the circumference. |
Diameter is Krishnavedala‘s own work is under the CC0 1.0 license, via Wikimedia Commons. |
| Part of Grammar: | |
| Noun
Plural: circumferences |
Noun
Plural: diameters |
The enclosing boundary of a curved geometric figure, especially a circle
The length of such a boundary |
A straight line passing from side to side through the center of a body or figure, especially a circle or sphere
[Physics] A unit of linear measurement of magnifying power [Mathematics] A chord passing through the center of a figure or body |
| Examples: | |
| The circumference of a circle is equal to π times the diameter.
Some babies have small head circumferences. Paul had a gold watch-face with diamond chips around its circumference. It was two inches in circumference. Columbus wasn’t the only one who got it wrong; many later attempts continued to produce different measurements for the earth’s circumference — even though the Greeks had calculated it correctly way back in the 3rd century B.C.. It was 10 miles from the center to the circumference of the sphere. |
Could you measure the diameter of that circle?
“The horizontal diameter was fifty feet, and the vertical diameter seventy-five feet” (Verne). The kids dug a hole nearly four feet in diameter. “Ultrasonographic measurements in 300 singleton pregnant women included biparietal diameter (cm), head circumference (cm), abdominal circumference (cm), femur length (cm) and transverse cerebellar diameter (cm)” (Mishra). The diameter of a human hair is approximately 50 μm. An object one millimeter wide magnified 40 diameters appears 40 millimeters wide. “The diameter is the longest chord possible in a circle and it divides the circle into two equal parts” (Chord). |
| Derivatives: | |
| Abbreviation: c, circ. Adjective: circumferential |
Abbreviation: d, diam. Adjective: diametral |
| History of the Word: | |
| Late Middle English from the Old French circonference, from the Latin circumferentia, which is from circum (around, about) + ferre (carry, bear). | Late Middle English from the Old French diametre, via the Latin from the Greek diametros (grammē) (line) measuring across, from dia (across) + metron (measure). |
C’mon, get it out of your system, bitch, whine, moan . . . which words are your pet peeves? Also, please note that I try to be as accurate as I can, but mistakes happen or I miss something. Email me if you find errors, so I can fix them . . . and we’ll all benefit!
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Resources for Circumference versus Diameter
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Apple Dictionary.com
“Chord Of A Circle, Its Length and Theorems.” Byju’s. n.d. Web. 4 Jan 2023. <https://byjus.com/maths/chord-of-circle/>.
The Free Dictionary: diameter
Merriam-Webster: circumference, diameter
Mishra, Sanjay Mishra, Surajit Ghatak, Pratibha Singh, Dushyant Agrawal, and Pawan Garg. “Transverse Cerebellar Diameter: A reliable predictor of gestational age.” National Center for Biotechnology Information. 20 Dec 2020. Web. 4 Jan 2023. <URL>. Article.
Verne, Jules. Five Weeks in a Balloon. Originally published in 1863. Jazzybee Verlag: 2014. <https://amzn.to/3CiaR1e>. Ebook.
Pinterest Photo Credits:
Diameter Circumference Ruler is a compressed file and is MikeRun‘s own work is under the CC BY-SA 4.0 license, via Wikimedia Commons. The black bands in the diameter were changed to purple to emphasize the difference.
