Arrange means to organize things in a particular order or position, or to make plans for something to happen. When you arrange books on a shelf, you might put them in alphabetical order or group them by size. When a florist arranges flowers in a vase, she positions them so they look beautiful together.

The word also means setting up plans or making something happen through coordination. If your parents arrange a playdate, they contact another family and agree on a time and place. A teacher might arrange a field trip by booking the bus, getting permission, and organizing chaperones. Companies arrange meetings, families arrange reunions, and orchestras arrange music by adapting it for different instruments.

An arrangement is both the result of arranging things (like a flower arrangement) and an agreement or plan between people (like an arrangement to carpool to school). Notice that arranging requires thought and purpose: you're making deliberate choices about how things should be organized or how plans should unfold. When something is well arranged, everything fits together smoothly and makes sense.