1. of, relating to, or along a diameter; passing through the center of a circle or sphere
2. completely opposite in character or nature; directly contrary

Examples

• The two points lie on a diametral line across the circle.
• Their political views are diametral opposites.
• The company's new strategy is diametral to its previous approach.
• A diametral cut through the sphere divides it into two equal halves.
• The twins have diametral personalities—one is outgoing and the other is shy.
• The diametral distance across the planet is approximately 12,742 kilometers.