Ill-tempered means having a tendency to become angry, irritable, or grumpy easily. An ill-tempered person snaps at others over small problems, complains frequently, and generally makes those around them feel tense or uncomfortable.

You might notice an ill-tempered teacher glaring when students ask questions, or an ill-tempered neighbor who yells about every little noise. The word suggests that this crankiness isn't just a bad day: it's part of someone's regular personality. An ill-tempered dog might growl when you walk past, while a friendly dog would wag its tail.

Its opposite would be even-tempered or good-natured.

In stories, ill-tempered characters like Ebenezer Scrooge or the Queen of Hearts show how unpleasant constant grumpiness makes someone to be around. Most people have moments of irritability when they're tired or frustrated, but truly ill-tempered people can seem to walk around with a storm cloud permanently overhead.