Takeout double

In the card game contract bridge, a takeout double is a low-level conventional call of "Double" over an opponent's bid as a request for partner to bid his best of the unbid suits. The most common takeout double is after an opponent's opening bid of one of a suit where the double shows a hand with opening values, support for all three unbid suits (at least three cards in each) and shortness in the suit doubled (preferably, no more than two). Normally, the partner of the doubler must bid his best suit but may pass if (a) his right hand opponent intervenes or (b) on the more rare occasions when his hand is such that he wishes to convert the takeout double to a penalty double.