quick-tempered

The compound adjective "quick-tempered" is a relatively modern English formation, emerging in the 18th century. It combines "quick" in its evolved sense of "rapid" with "temper," which originally meant a balanced mixture or constitution. The logic of the word is transparent: it describes a person whose "temper" or state of mind shifts to anger with "quick" speed. This construction follows a common English pattern for personality traits, such as "good-tempered" or "short-tempered," where an adjective modifies the noun "temper" to specify the nature of one's emotional reactivity.

Structure: quick (fast) + temper (mood) + ed (adjective suffix) - quick: From Old English cwic (alive, living, animated), with the sense of rapid motion developing in Middle English. In this compound, it functions as an intensifier meaning "rapidly occurring." - temper: From Latin temperare (to mix, regulate, moderate). Via Old French temprer and Middle English, it came to mean the character or mood of a person, specifically the balance of humors. Here, it refers to one's state of mind or disposition. - ed: A common English suffix forming adjectives from nouns or verbs, indicating "having the quality of."