Definition of muriatic acid in US English:

muriatic acid


  • archaic term for hydrochloric acid
    • ‘When I was a kid, my dad used muriatic acid to clean hard-water stains from the family bathtub.’
    • ‘If the mortar smears still remain, wait a week (until the masonry cures) and clean with a solution of one part muriatic acid to nine parts water, mixed in a plastic bucket.’
    • ‘In the two wet cleaning systems, no muriatic acid or compounds containing muriatic acid may be used.’
    • ‘Any eye contact with muriatic acid solution should be followed immediately by irrigating the eyes with plenty of water.’
    • ‘If the floor is not flushed thoroughly with water after clean up, the muriatic acid will continue to leach lime from the grout causing the whitish dust.’


Late 17th century: muriatic from Latin muriaticus, from muria ‘brine’.


muriatic acid

/ˌmyo͝orēˌadik ˈasəd/