An interchange is a place where major roads or highways cross each other, designed so traffic can switch from one road to another without stopping at traffic lights. Picture a highway junction with curving ramps that loop over and under each other, letting cars smoothly move between roads going different directions. These engineering marvels let thousands of vehicles change routes safely at high speeds.

The word can also mean to exchange or swap things. Two students might interchange ideas during a class discussion, each sharing thoughts and building on what the other says. In basketball, teammates might interchange positions depending on what the play requires. When parts are interchangeable, it means they can be swapped: your bike's front and rear wheels are often interchangeable because they're built the same way.

In both meanings, the core idea is the same: things moving between positions, switching places, or connecting in ways that let them flow smoothly from one state or location to another.