"To enclose the shower" means to put something around the shower area to keep water from splashing out and to provide privacy while you shower. Full definition
The new master bath gets updated with glass enclosed shower with granite tile, a stone tile floor and an adjacent walk - in closet. (hgtv.com)
The two marble bathrooms include two large sink a bathtub and a glass enclosed shower with rain shower. (pfitravel.com)
The bathroom was clad in marble and had a pedestal sink next to a glass enclosed shower stall that was supplied with ample water pressure. (frequentbusinesstraveler.com)