What is a certain number of balls (usually four) delivered successively from behind ine wicket, after which the ball is bowled from behing the other wicket as many times, the fielders changing places called?

over — A certain number of balls (usually four) delivered successively from behind ine wicket, after which the ball is bowled from behing the other wicket as many times, the fielders changing places. (Webster's 1913.)

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