big gun

Noun

 * 1)  A large artillery gun or one of the largest-caliber naval guns (as on a battleship).
 * 2)  A person, group, thing, or course of action that is powerful, influential, or particularly effective.
 * 3) * 1957 Aug. 28, Ed Wilks, "Sports" (Headline), Park City News (USA), p. 15 (retrieved 20 Aug. 2011) :
 * Berra Is Big Gun In Yankee Victory
 * 1)  A person, group, thing, or course of action that is powerful, influential, or particularly effective.
 * 2) * 1957 Aug. 28, Ed Wilks, "Sports" (Headline), Park City News (USA), p. 15 (retrieved 20 Aug. 2011) :
 * Berra Is Big Gun In Yankee Victory
 * 1) * 1957 Aug. 28, Ed Wilks, "Sports" (Headline), Park City News (USA), p. 15 (retrieved 20 Aug. 2011) :
 * Berra Is Big Gun In Yankee Victory
 * Berra Is Big Gun In Yankee Victory