1350–1400; Middle English diametre < Old French < Latin diametros < Greek diámetros diagonal, diameter, equivalent to dia- dia- + -metros, derivative of métron meter1 (Source: dictionary.com)
Late Middle English from Old French diametre, via Latin from Greek diametros (grammē) ‘(line) measuring across’, from dia ‘across’ + metron ‘measure’. (Source: lexico.com)
Definitions of Diameter
Geometry. a straight line passing through the center of a circle or sphere and meeting the circumference or surface at each end. a straight line passing from side to side of any figure or body, through its center.
the length of such a line.
the width of a circular or cylindrical object.
a straight line connecting the centre of a geometric figure, esp a circle or sphere, with two points on the perimeter or surface the length of such a line
the thickness of something, esp with circular cross section
A straight line connecting two opposite points on the surface of a spherical or cylindrical body, or at the boundary of an opening or foramen, passing through the center of such body or opening.
The distance measured along such a line.
A straight line passing from side to side through the centre of a body or figure, especially a circle or sphere.
A unit of linear measurement of magnifying power.
: a chord (see chord entry 3 sense 2) passing through the center of a figure or body
: the length of a straight line through the center of an object or space the diameter of a circle dug a hole nearly four feet in diameter
: a unit of enlargement used with a number to indicate magnification by a lens or optical system an object one millimeter wide magnified 40 diameters appears 40 millimeters wide
Example sentences for Diameter
Kepler-186f is about 11 percent larger than Earth in diameter, which means it has nearly 25% more surface area.
An array of whittled bamboo sticks, each four millimeters in diameter, makes up the two-room installation.
The doctors discovered the entry wound into the frontal lobe with a diameter about equal to that of a cigarette.
Using a 2-inch (5cm) diameter ring cutter, cut the scallops into straight cylinders; reserve the trim.
Pi is officially defined as the ratio of the circumference of a circle to its diameter.
Today the seven Centennial trees are about two feet in diameter and about 60 feet high.
It is enveloped in a delicate vesicle, the diameter of which is very much greater than that of the contained ovum.
Many of the pines on this ridge were two feet in diameter, and a hundred feet high, with small clusters of limbs around the tops.
This lake was nearly round, and probably somewhat less than one-half mile in diameter.
All along the side of the road extended an array of huge new pipes, some three feet in diameter, awaiting their turn underground.