Cantankerous means bad-tempered, argumentative, and difficult to deal with. A cantankerous person complains frequently, argues over small things, and seems determined to be disagreeable no matter what's happening.

You might know a cantankerous character from a book or movie: someone who grumbles about everything, snaps at people for no good reason, and treats every minor inconvenience like a major disaster. In A Christmas Carol, Ebenezer Scrooge starts out cantankerous, growling “Bah, humbug!” at anything cheerful. The word often describes older people who've grown grouchy over the years, though anyone can act cantankerous when they're in a foul mood.

Someone who's cantankerous seems to wake up looking for things to complain about, carrying their bad mood into everything they do. If your normally pleasant grandfather becomes cantankerous one morning, criticizing breakfast, arguing about the weather, and finding fault with everyone around him, you might wonder what's bothering him. A cantankerous mood can color everything with irritability.

The word has a distinctive sound that matches its meaning: those harsh consonants feel as prickly as a cantankerous person's personality. When someone's being cantankerous, they approach disagreements with stubborn contrariness and make everything harder than it needs to be, turning simple interactions into exhausting conflicts.