means A liquid or semi-liquid preparation applied to the skin to moisturize, soothe, or treat it.

from From Latin 'lotio,' meaning 'a washing,' which comes from 'lavare,' 'to wash' — the same root that gives us 'launder,' 'lavatory,' and 'lather.' It slipped into English through Old French around the late Middle Ages, originally meaning a medicinal wash for wounds and ailments long before it became the bottle you squeeze onto dry knuckles.