Wiktionary
bath salt
n. 1 (context chiefly in the plural English) Any of several inorganic salts sometimes added to bath water. 2 (context slang psychedelic drug culture English) Any of a class of methylenedioxypyrovalerone-based psychoactive recreational drugs.
Usage examples of "bath salt".
The heady scent of their lovemaking dissipated, to be replaced by the fragrance of her favorite bath salt.