The meaning of optional is involving an option : How to use optional in a sentence. If something is optional, you can choose if you want to do it, pay it, buy it, etc.:
Optional synonyms, optional pronunciation, optional translation, english dictionary definition of optional. See examples of optional used in a sentence. Definition of optional adjective in oxford advanced learner's dictionary.
Optional in american english (ˈɑpʃənəl ) adjective left to one's option, or choice; The power or right of choosing:[uncountable] to have no option but to stay. Optional refers to something that is not compulsory or required, and can be chosen at one's own discretion or preference.
If you can choose whether or not to do something, it is optional. Extra credit is always optional;