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fac·ul·ta·tive | \ ˈfa-kəl-ˌtā-tiv 
, British -tə-tiv \
, 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
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More Definitions for facultative
facultative
adjectivefac·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
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The first known use of facultative was in 1820
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