Abstract: Trousers or a combination wear composed of an upper wear portion and a trouser portion, wherein the trousers or the trouser portion of the combination wear is openable at a root portion thereof by a slide fastener along a U-shaped center line thereof starting from a back upper edge of the trousers or a corresponding back center point positioned between the trouser portion and the upper wear portion towards a front upper portion of the trousers or a corresponding front center point positioned between the trouser portion and the upper wear portion through a lowest point of the U-shaped center line. Further, the slide fastener may be a double slide fastener openable from both ends so that the root portion is also openable starting from the front upper portion of the trousers or the front center point positioned between the trouser portion and the upper wear portion.