A rooster is an adult male chicken, known for its bold personality and its loud crowing at dawn. While hens lay eggs, roosters protect the flock and announce the morning with their distinctive “cock-a-doodle-doo” call. They sport brightly colored feathers, a red comb on top of their head, and a wattle (the fleshy red part) hanging below their beak.

Roosters have strutted through farms for thousands of years, serving as natural alarm clocks long before electricity. Their morning crow signals the start of a new day, which is why people sometimes call early risers who wake up full of energy “roosters.” If your brother bounds out of bed at 6 AM ready to play, your parents might joke that he's “up with the roosters.”

The word also appears in expressions: when someone acts overly proud or aggressive, you might say they're being cocky. A rooster tail describes the spray of water behind a speedboat, named for its resemblance to a rooster's dramatic tail feathers.