sauna

noun

1. a bath that uses dry heat to induce perspiration, and in which steam is produced by pouring water on heated stones.
2. a bathhouse or room, usually of wood, equipped for such a bath.

verb (used without object), sau·naed, sau·na·ing.

3. to take a sauna: to sauna after exercising.

noun

1. an invigorating bath originating in Finland in which the bather is subjected to hot steam, usually followed by a cold plunge or by being lightly beaten with birch twigs
2. the place in which such a bath is taken

n.1881, from Finnish sauna.