facultative [ fak-uh l-tey-tiv ]
1. conferring a faculty, privilege, permission, or the power of doing or not doing something: a facultative enactment.
2. left to one's option or choice; optional: The last questions in the examination were facultative.
3. that may or may not take place; that may or may not assume a specified character.
4. Biology. having the capacity to live under more than one specific set of environmental conditions, as a plant that can lead either a parasitic or a nonparasitic life or a bacterium that can live with or without air (opposed to obligate).
5. of or relating to the faculties.
fac·ul·ta·tive·ly , adverb
non·fac·ul·ta·tive , adjective
discretionary, elective, volitional, voluntary, discretional
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Origin: From the New Latin word facultātīvus, dating back to 1810–20. See faculty, -ive
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