optional
noun
Definitions
Something that is not compulsory, especially part of an academic course.
(sometimes capitalized) In various programming languages, a kind of variable that is assigned a specific data type but may or may not hold an actual value.
adjective
Definitions
Not compulsory; left to personal choice; elective.
Example: On that beach clothing is entirely optional.
Synonyms:facultativeAntonyms:compulsorymandatoryobligatory