A grip comprises a grip body forming a gripping control portion of a manually operable device to be held with the operator's palm and fingers. The grip body includes a ball-receiving surface coming into contact with the ball of the thumb, a palm-receiving surface coming into contact with a middle portion of the palm and the ball of the little finger, a finger-receiving surface coming into contact with the fingers, an open surface positioned between the tips of the fingers and the ball of the thumb for receiving the thumb when the grip body is held, and a switch mounted on a top portion of the grip body to be operable with the thumb. The grip body further comprises a thumb-guiding portion in the form of a shallow groove formed at an upper part of the ball-receiving surface of the grip body, the inside of the first joint of the thumb being placed along the thumb-guiding portion when the switch is operated, and a rising portion formed on at least either one of portions between the thumb-guiding surface and the open surface and between the thumb-guiding surface and the palm-receiving surface for applying resistance when the operator's hand advances into the switch.