What does temperamental mean?
Temperamental means likely to change suddenly and unpredictably in mood, temper, or behavior. Applied to people, it suggests someone whose emotions or reactions can shift rapidly, often with impatience or irritability, so the term may sound faintly judgmental even when intended as a description. It can also describe machinery, instruments, performances, or systems whose performance is erratic and difficult to control. The word derives from temper, an older term for a person's characteristic disposition, reflecting its long history of linking character or constitution with stability. In contemporary use, temperamental is more specific than simply emotional: it implies inconsistency or unpredictability rather than a sustained state of sadness, excitement, or anxiety. It is especially common in conversation, criticism, and biography, where writers describe performers, artists, children, or machines as difficult to manage. Although often used lightly, the word can characterize temperament rather than conduct, distinguishing a person's variable disposition from any single emotional episode. Its usefulness lies in capturing a repeated pattern of change rather than an isolated outburst, making it a vivid label for anything known to be erratic or resistant to regularity.
adjectiveLiable to sudden and unpredictable changes in mood, temper, or behavior. It can also describe machinery, performances, or systems that behave erratically or are difficult to control.
- Subject to sudden, often extreme, changes of mood, temper, or behavior.
- Unpredictable or erratic in operation, performance, or behavior.
- Historically, relating to or characterized by a person's temperament or constitution.
"The acclaimed actor was famously temperamental, charming one night and impossible to direct the next."
"His temperamental behavior made rehearsals tense but also produced some of the performance's most memorable moments."
"The old synthesizer became temperamental whenever the room grew humid."
Temperamental began as a neutral label for someone's underlying temperament, but its modern fame rests on a less neutral implication: unpredictability.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does temperamental come from?
Temperamental was formed in English in the early 17th century from temper and the suffix -al, initially meaning related to temperament. Temper came through Anglo-French from Latin temperare, meaning to mix, moderate, or regulate, which also underlies temperament, temperate, and temperature. The modern emphasis on emotional unpredictability developed from the older association between temperament, disposition, and physical or mental constitution.
Related word forms
How temperamental is actually used
Common in both formal and informal English. When applied to people, it can sound mildly pejorative and often implies irritability or emotional volatility; for instruments, vehicles, or performances, it emphasizes erratic and unreliable behavior.
Easily confused with temperamental
Temperament is a noun referring to a person's characteristic disposition, while temperamental is an adjective describing someone or something as volatile, erratic, or unpredictable.