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

Taking notes from this fashion capital isn’t optional, but essential. —Amanda Le, InStyle, 4 Mar. 2026

When commercial recycling is optional, Willis said between 20% and 25% of businesses participate. —Steve Sadin, Chicago Tribune, 4 Mar. 2026

The Truck’s standard battery is said to provide up to 150 miles of range on a single charge; an optional larger battery extends that to 240 miles. —ABC News, 4 Mar. 2026

Williams explains that the organization intentionally brings together leaders who would not typically meet people from different sectors, communities, and lived experiences, and places them in structured environments where listening is not optional. —Daniel Fusch, USA Today, 4 Mar. 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