optional

adjective

op·​tion·​al ˈäp-sh(ə-)nəl 

: involving an option : not compulsory

optionality

ˌäp-shə-ˈna-lə-tē 

noun

optionally adverb

Synonyms of optional

• voluntary
• elective
• discretionary

Examples of optional in a Sentence

Jackets are required at the restaurant, but ties are optional.

Many optional features are available on this car.

Registration is optional, not mandatory.

Recent Examples on the Web

In a recent conversation with Peter Diamandis, an entrepreneur and executive chairman of the XPrize Foundation, Musk fleshed out his moonshot visions for the future, which have previously included work being completely optional and retirement becoming inapplicable. —Sasha Rogelberg, Fortune, 12 June 2026

Columbia is the only Ivy League holdout for test-optional undergraduate admissions. —Dr. Marlena Corcoran, Forbes.com, 12 June 2026

Many home warranty providers offer plans that include central air conditioning systems as part of their standard coverage or as an optional add-on. —Angelica Leicht, CBS News, 12 June 2026

Columbia went test-optional in 2020 as standardized testing centers temporarily closed during the COVID-19 pandemic and critics raised equity concerns. —Cayla Bamberger, New York Daily News, 12 June 2026

Word History

First Known Use

1765, in the meaning defined above

Kids Definition

optional

adjective

op·​tion·​al ˈäp-shnəl 

-shən-ᵊl

: left to one's choice : not required

optional equipment on a new car

optionally

-ē

adverb