To occur in turn repeatedly. The weather alternates between sunny and rainy throughout the week.
To switch back and forth between two or more things. She alternates between jogging and cycling for her daily exercise.
To take turns doing something. They alternate driving duties on long road trips.
To cause two or more things to follow each other in turn; to intersperse or arrange in alternating order. The designer alternated stripes of blue and white across the wall.