Compact means tightly packed together or taking up little space. A compact car is smaller than a full-size sedan, making it easier to park in tight spots. When you pack for a trip, you might compress your clothes into a compact bundle so they fit in your suitcase. A compact disc (CD) got its name because it could store lots of music in a small, flat circle.

The word can also describe writing or speaking that says a lot without wasting words. A compact explanation gets right to the point. Some essays are long and rambling, while others are compact and efficient, delivering the same ideas in half the space.

As a noun, a compact is a formal agreement between people or groups. The Mayflower Compact was an agreement the Pilgrims signed before landing in North America, establishing rules for their new colony. When two friends make a compact to study together every Tuesday, they're creating a serious promise, not just a casual plan.

The verb form means to press something together tightly. Trash collectors compact garbage to fit more in their trucks. Snow gets compacted into ice when many feet walk over it.