Definition of "diameter" in English

noun

1. (geometry) Any straight line between two points on the circumference of a circle that passes through the centre/center of the circle; a chord that passes through the center of the circle.

2. (geometry) The length of such a line.

3. (geometry) The maximum distance between any two points in a metric space.

4. (graph theory) The maximum eccentricity over all vertices in a graph.