口水
kǒushuǐ · HSK 7
saliva
💧👄 口水 = mouth (口) + water (水); the water from your mouth is saliva
口 is mouth and 水 is water, so 口水 literally reads as mouth-water, the everyday word for saliva or spit. The same mouth-plus-something pattern shows up in other body-fluid compounds.
口 — pictograph of an open mouth
口 is one of the oldest pictographs in Chinese, originally drawn as a simple outline of an open mouth. Its core meaning 'mouth' extended naturally to 'opening' or 'entrance', as in 入口 (entrance). It also serves as a common radical in characters related to speech, eating, or apertures.
水 — pictograph of flowing water
水 is a pictograph depicting a stream of flowing water, with the central line representing the main current and the side strokes showing splashing droplets or ripples. In oracle bone script it was drawn even more clearly as a wavy vertical line with branches. It retains its original meaning of 'water' and also serves as a radical, often appearing in the compressed form 氵.