1. to occur in turns; to switch back and forth between two or more things
2. to cause to occur in turns; to arrange in succession

1. people who serve as substitutes or replacements

Examples

• The traffic light alternates between red and green.
• She alternates between working from home and the office.
• The coach alternates the starting lineup each game.
• We need to find alternates for the committee members who can’t attend.
• The alternates will step in if any regular players are injured.
• Day alternates with night in a regular cycle.
• The teacher alternates between lectures and group activities.