Definition of circumference in US English:


(also circum., circ., cir.)


  • 1The enclosing boundary of a curved geometric figure, especially a circle.

    • ‘It can be shown by geometry that the radius of a circle will inscribe six equal chords within the circumference of the circle.’
    • ‘Pi, whose decimal value is 3.1415926535…, is simply the ratio of the circumference of a circle to its diameter.’
    • ‘The letters spelling out Canadian Security Investigative Service were in big white bold letters around the circumference of the circle.’
    • ‘The 18th-century Chinese scholar Tai Chen presented an elegant dissection for approximating the value of pi - the ratio of a circle's circumference to its diameter.’
    • ‘We should have a polygon inscribed in the circle the sides of which coincide with the circumference of the circle.’
    • ‘The perimeter of the inner polygon is shorter than the circumference of the circle.’
    • ‘As a result of this activity, students may or may not discover that the diameter and the circumference of the circle stand in a linear relationship.’
    • ‘At its simplest, pi is the ratio of the circumference of a circle to its diameter.’
    • ‘We will locate a marker on the circumference of a circle.’
    • ‘The mathematical constant pi is the number you get when you divide a circle's circumference by its diameter.’
    • ‘I've long since forgotten quadratic equations and how to calculate the circumference of a circle.’
    • ‘His last work was on the cycloid, the curve traced by a point on the circumference of a rolling circle.’
    • ‘We would regard the starting point as the easternmost point along the circumference of the circle.’
    • ‘Taking a circle of diameter 10,000,000 chang, he found the circumference of this circle to be less than 31,415,927 chang and greater than 31,415,926 chang.’
    • ‘Galileo established the circumference of the larger circle by restricting the subject matter of physics to statements about primary qualities.’
    • ‘Since E lies on the circumference of both circles, it is located at one of the points of intersection.’
    • ‘In the normal geometry of flat space, the diameter of a circle is its circumference divided by pi.’
    • ‘He regretted that an exact measure of the circumference of a circle in terms of diameter was not available.’
    • ‘Spanish swordsmen attack and defend by stepping around each other along the circumference of the circle.’
    • ‘In maths today they could not work out the circumference of a circle.’
    perimeter, border, boundary
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    1. 1.1 The distance around something.
      ‘babies who have small head circumferences’
      ‘two inches in circumference’
      • ‘The World Health Organization standards for waist and hip circumferences are based on measurements made in the standing position.’
      • ‘He has travelled more than 774,200 miles on trips in Italy and abroad, equivalent to nearly 30 times the circumference of the earth.’
      • ‘Each subject was placed in the supine position, and upper arm and wrist circumferences were measured to determine proper cuff size.’
      • ‘Measure the circumference of your head in inches and see what you get!’
      • ‘The winner of the under ten category was Scarlet, whose pumpkin had a circumference of 57 inches.’
      • ‘The length of the collar should be approximately two inches longer than the circumference of the dog's neck.’
      • ‘The circumference of my thighs was reduced by between half and a quarter of an inch.’
      • ‘You would do better to cut out a large circle of wood and use a tape measure to find its circumference and diameter.’
      • ‘Measure the circumference of your wrist where the bracelet will be worn.’
      • ‘You can walk the entire circumference, a distance of 1.3 km.’
      • ‘Men should have a waist circumference less than 40 inches.’
      • ‘Maternal arm and calf circumferences were measured with plastic-covered fabric measuring tapes and read to the nearest millimeter.’
      • ‘One commonly used method for quantifying differences in body fat distribution is to measure and comopute the ratio of the waist circumference to the hip circumference.’
      • ‘After measuring a drum shade, add 1 inch to the circumference and 3 inches to the height.’
      • ‘Calculating your body mass index and measuring your waist circumference are two ways to help tell if you're overweight or obese.’
      • ‘I had to measure the circumference and calculate the diameter to make sure it would fit in and out of my doorway!’
      • ‘A search for a new teak wood tree of the required circumference and length began.’
      • ‘A hailstone with a 7-inch diameter and a circumference of 18.75 inches was recently named the largest hailstone ever recovered in the United States.’
      • ‘Waist circumferences of 35 inches or greater in women have been associated with increased health risks.’
      • ‘They had these peculiar heels that were of a similar circumference to a ballpoint pen, and were about six inches in depth.’
      girth, width
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Late Middle English: from Old French circonference, from Latin circumferentia, from circum ‘around, about’ + ferre ‘carry, bear’.