The word 口渴 (kǒu kě), meaning "thirsty", is a compound word formed by combining two meaningful characters: 口 (kǒu), which means "mouth", and 渴 (kě), which means "thirsty" or "to thirst". It is a descriptive or coordinative compound where the first character specifies the body part (口/mouth) and the second character describes its state (渴/thirsty), literally conveying the sensation of "mouth-thirst" to express the physical feeling of needing to drink.