facultative

adjective
fac·​ul·​ta·​tive | \ ˈfa-kəl-ˌtā-tiv How to pronounce facultative (audio) , British -tə-tiv \

Definition of facultative

1a : of or relating to the grant of permission, authority, or privilege facultative legislation
b : optional
2 : of or relating to a mental faculty
3a : 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

Other Words from facultative

facultatively adverb

Examples of facultative in a Sentence

Recent Examples on the Web Because cleaner fish have other food sources besides the parasites, such as crustaceans, this relationship is also facultative mutualism. Liz Langley, National Geographic, 25 Sep. 2020 Ball pythons are native to central and western Africa and can reproduce asexually, which is known as facultative parthenogenesis, the zoo said. David Williams, CNN, 11 Sep. 2020 The dragon’s birth, which came during a study of fertility, was said to result from a special type of parthenogenesis, called facultative parthenogenesis. Martin Weil, Washington Post, 6 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'facultative.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of facultative

1820, in the meaning defined at sense 1a

History and Etymology for facultative

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

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Time Traveler for facultative

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The first known use of facultative was in 1820

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Dictionary Entries Near facultative

facula

facultative

facultative referendum

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Cite this Entry

“Facultative.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/facultative. Accessed 1 Jul. 2022.

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More Definitions for facultative

facultative

adjective
fac·​ul·​ta·​tive | \ ˈfak-əl-ˌtāt-iv How to pronounce facultative (audio) \

Medical Definition of facultative

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

Other Words from facultative

facultatively adverb

More from Merriam-Webster on facultative

Nglish: Translation of facultative for Spanish Speakers

Britannica English: Translation of facultative for Arabic Speakers

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