man cave
noun Informal.
a room or other area in a home that is primarily a male sanctuary, designed and furnished to accommodate the man's recreational activities, hobbies, etc.: The basement is my husband's man cave—during football season, you can usually find him down there watching the game with his buddies on the big-screen TV.
Origin:
1990–95
Hello Cave Dwellers! Welcome to our new Man Cave Website. "The Official Man Cave Site, LLC" changed the website to focus its efforts on Man Caves and its members. We welcome you to create an account and post photos of your Man Cave. Look around and let us know what you think and how we can improve this site.
Cave On!
Mike