Definition of diameter
- the diameter of a circle
- dug a hole nearly four feet in diameter
- an object one millimeter wide magnified 40 diameters appears 40 millimeters wide
The dotted line indicates the diameter of the circle.
What is the diameter of the tree trunk?
Dig a hole that's two feet deep and three feet in diameter.
These example sentences are selected automatically from various online news sources to reflect current usage of the word 'diameter.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.
: a straight line from one side of something (such as a circle) to the other side that passes through the center point
: the distance through the center of something from one side to the other
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