A beater is something or someone that beats or strikes repeatedly. The word has several common meanings:

1. A kitchen tool used for mixing ingredients. An egg beater whips eggs or cream by spinning wire loops through them rapidly. Electric mixers have beaters that rotate to blend cake batter or cookie dough. When a recipe says to beat the eggs until fluffy, you're using quick, repeated strokes to mix air into them.
2. An old, worn-out car that still runs but looks rough and needs frequent repairs. Someone might drive a beater to school instead of risking their nice car in the student parking lot. The term suggests a vehicle that's been beaten up by time and use but keeps going. A beater isn't pretty, but it gets you where you need to go.
3. In hunting, a person who walks through woods or fields making noise to drive game birds toward the hunters. Beaters help flush out pheasants or grouse by beating bushes and making commotion.