Optional means not required or mandatory. Something optional is a choice you can make rather than something you have to do. When a teacher assigns optional homework for extra practice, you can decide whether to complete it based on whether you need the practice or have the time. When a car comes with optional features like heated seats or a sunroof, buyers can choose to add them or not.

The opposite of optional is required or mandatory. Reading the assigned chapter is required, but reading the author's other books is optional. Wearing your seatbelt is mandatory, but listening to music during the drive is optional.

Understanding what's optional versus required helps you make decisions about how to spend your time and energy. Optional activities like joining the chess club or signing up for the school talent show let you explore interests without pressure.