noun
radar gun; speed gun
A device that uses radar to measure the speed of a moving object, such as a vehicle or a pitched baseball. The term is rare in Japanese; スピードガン is the more common equivalent.
See also: スピードガン
警察がレーダーガンで車の速度を測定した。
The police measured the car's speed with a radar gun.
野球の試合で、スカウトがレーダーガンを使って投手の球速を計っていた。
At the baseball game, scouts were using a radar gun to measure the pitcher's speed.