tub-fast

tub-fast

n
(in the past) a period of fasting and sweating in a hot tub, intended as a cure for venereal disease
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014