Grouse is both a type of bird and a verb meaning to complain.

The grouse is a plump game bird that lives in forests, mountains, and moorlands across North America, Europe, and Asia. These birds are known for their mottled brown and gray feathers that help them blend into their surroundings. Male grouse make distinctive drumming sounds by rapidly beating their wings, which can be heard echoing through the woods during mating season. Hunters prize grouse as challenging quarry because the birds explode into flight when startled, requiring quick reflexes.

To grouse also means to complain or grumble, usually about something minor. When someone grouses about their chores, the cafeteria food, or having to wake up early, they're expressing irritation in a whiny or cranky way. Unlike making a legitimate complaint or standing up for something important, grousing is more like muttering under your breath about things that bother you but probably aren't going to change.

When your friend grouses about homework for the tenth time, they're not actually trying to fix anything. They're just venting their frustration.