also: すいぶろ
The Edo-period mizuburo was a type of fixed bathtub heated by a fire built underneath.
Standard kanji spelling for this historical term.
Alternate reading すいぶろ; less common than すいふろ.
Compound of 水 (mizu, 'water') and 風呂 (furo, 'bath'). The exact historical derivation is uncertain; the term refers to a bathtub where water was heated directly by a fire underneath.