facultative

adjective fac·ul·ta·tive \ ˈfa-kəl-ˌtā-tiv , British -tə-tiv \

Definition of facultative

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

Origin and Etymology of 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


Medical Dictionary

facultative

adjective fac·ul·ta·tive \ ˈfak-əl-ˌtāt-iv \

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

facultatively

adverb


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