optional

[op-shuh-nl] /ˈɒp ʃə nl/

adjective

left to one's choice; not required or mandatory:

Formal dress is optional.

leaving something to choice.

Origin

1755-65; option + -al¹

Related forms

optionality, noun

optionally, adverb

nonoptional, adjective

nonoptionally, adverb

unoptional, adjective

unoptionally, adverb

Synonyms

1. discretional, elective, voluntary.

Examples from the web for optional

When nominations are made it is optional whether they are seconded or not.
We may give others a preference over him in optional good offices, except those which tend to his improvement.
Shellfish are optional, but always add glamour and color if you wish to include them.
Frying the crab first is optional, but it adds superb flavor and makes the crabmeat more tender.
Under the first version of the new plan, the département number was to have been an optional add-on.
And, by the way, an optional alternative tax system is not simple.
For insurers: an optional system of federal chartering and regulation, aimed primarily at protecting their safety and soundness.
Students then follow optional concentrations in the second year.
The programme begins with optional pre-programme courses in statistics and mathematics.
optional information such as your age or gender may also be requested.

British Dictionary definitions for optional

/ˈɒpʃənəl/

adjective

possible but not compulsory; left to personal choice

Derived Forms

optionally, adverb

Word Origin and History for optional

adj.

1765, from option + -al (1).