sitz bath
noun
ˈsits- 
: a tub in which one bathes in a sitting posture
also : a bath so taken especially therapeutically
Example Sentences
Recent Examples on the Web Hemorrhoids can be pretty responsive to over-the-counter creams, an ice pack, soaking in a sitz bath, or using a suppository with corticosteroid creams to alleviate pain and swelling. 
Rozalynn S. Frazier, SELF, 10 Mar. 2022 One small study even suggests that bidets may even prompt some muscle relaxation, though most people seeking that sort of comfort might be better off opting for a sitz bath or a long soak in a tub of warm water. Katherine J. Wu, Smithsonian Magazine, 20 May 2020
Rozalynn S. Frazier, SELF, 10 Mar. 2022 One small study even suggests that bidets may even prompt some muscle relaxation, though most people seeking that sort of comfort might be better off opting for a sitz bath or a long soak in a tub of warm water. Katherine J. Wu, Smithsonian Magazine, 20 May 2020 Word History
Etymology
partial translation of German Sitzbad, from Sitz act of sitting + Bad bath
First Known Use
1842, in the meaning defined above
Medical Definition
sitz bath
noun
ˈsits-
1
: a tub in which one bathes in a sitting posture
2
: a bath in which the hips and buttocks are immersed in hot water for the therapeutic effect of moist heat in the perineal and anal regions