facultative

adjective

fac·​ul·​ta·​tive ˈfa-kəl-ˌtā-tiv How to pronounce facultative (audio)
 British  -tə-tiv
1
a
: of or relating to the grant of permission, authority, or privilege
facultative legislation
b
: optional
2
: of or relating to a mental faculty
3
a
: taking place under some conditions but not under others
facultative diapause
b
: exhibiting an indicated lifestyle under some environmental conditions but not under others
facultative anaerobes
facultatively adverb

Examples of facultative in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
After heading several facultative roles at the company, Elamin serves as the head of facultative for Aon Reinsurance Solutions for the Middle East, Africa and Turkey. — Mckinley Franklin, People.com, 8 Jan. 2025 Unlike the Queensland lungfish, which is a facultative air-breather, the South American lungfish must breathe air to survive. — Scott Travers, Forbes, 15 Sep. 2024

Word History

Etymology

borrowed from French & New Latin; French facultatif, borrowed from New Latin facultātīvus, from Medieval Latin facultāt-, facultās "ability, power, authority, privilege, right" (Latin, "ability, power") + Latin -īvus -ive — more at faculty

First Known Use

1820, in the meaning defined at sense 1a

Time Traveler
The first known use of facultative was in 1820

Rhymes for facultative

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Cite this Entry

“Facultative.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/facultative. Accessed 23 Mar. 2025.

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Medical Definition

facultative

adjective
fac·​ul·​ta·​tive ˈfak-əl-ˌtāt-iv How to pronounce facultative (audio)
1
: taking place under some conditions but not under others
facultative parasitism
2
: exhibiting an indicated lifestyle under some environmental conditions but not under others
facultative anaerobes
facultatively adverb

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Nglish: Translation of facultative for Spanish Speakers

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