sauna
noun /ˈsɔːnə/,  /ˈsaʊnə/
  /ˈsɔːnə/,  /ˈsaʊnə/
 - a period of time in which you sit or lie in a room (also called a sauna) which has been heated to a very high temperature. Some saunas involve the use of steam.
- a hotel with a swimming pool and sauna
 - to have/take a sauna
 
Word Originlate 19th cent.: from Finnish.