To be ornery is to be grumpy and hard to please. Oscar the Grouch? Definitely ornery.
The adjective ornery sprung up in the early 19th century when people started pronouncing ordinary with an accent. The root of ordinary is the Latin word for “order,” and if you disrupt the orderly existence of an ornery person, prepare to get yelled at. A person can have a consistently ornery personality, or maybe you’re feeling ornery today because you skipped breakfast. Some synonyms for ornery are cantankerous and crotchety, words that sound as grumpy as the people they describe.