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The negative double is a form of takeout double in bridge. It is made by the responder after their right-hand opponent overcalls on the first round of bidding, and is used to show shortness in overcall's suit, support for the unbid suits with emphasis on majors, as well as some values. It is treated as forcing, but not unconditionally so. In practice, the negative double is sometimes used as a sort of catch-all, made when no other call properly describes responder's hand. Therefore, a partnership might even treat the negative double as a wide-ranging call that merely shows some values.