The Chinese word 失眠 (shīmián), meaning "insomnia", is a compound formed by combining two meaningful characters: 失 (shī), which means "to lose" or "to lack", and 眠 (mián), which means "sleep". Together, they create a logical and semantically transparent concept: the state of "losing sleep" or being unable to sleep. This follows a common pattern in Chinese word formation where a verb (失) modifies a noun (眠) to describe a condition or result, effectively and intuitively conveying the essence of the condition.