facultative
Able to adapt
Facultative describes something optional rather than obligatory, or capable of functioning under different conditions.
In biology, facultative organisms can adapt to varying environments—a facultative anaerobe survives with or without oxygen, unlike an obligate anaerobe that requires its absence.
The course includes facultative readings for students who want to go deeper.
Subject to personal judgment
- voluntaryDone by choice
- nonobligatoryNot compulsory or mandated
- noncompulsoryNot required by rule
- electiveChosen, not mandated
permissive · unrequired · nonmandatory · dispensable · waivable · at-will · negotiable · flexible
Conditional or representative group
- circumstantialBased on inference, not proof
- provisionalConditional and possibly temporary
- dependentRequiring outside support
- situationalDependent on circumstances
qualified · prerequisite · stipulation · proviso · hypothetical · eventuality · precondition · variable
Organism needing no oxygen
- parasiteOne exploiting a host
- symbiontOrganism sharing mutual benefit
- mutualistPartner in mutual benefit
- pathogenDisease-causing microorganism
saprophyte · heterotroph · organism · adaptation · metabolism · survival · opportunistic · commensal
Official permission to skip rules
- canonicalAccepted as standard
- beneficeEndowed clerical position
- privilegeExclusive right or benefit
- permissionGranted right to act
papal · bishop · clergy · authority · exemption · ecclesiastical · delegation
discretionary
Subject to personal judgment
- voluntaryDone by choice
- nonobligatoryNot compulsory or mandated
- noncompulsoryNot required by rule
elective · permissive · unrequired · nonmandatory · dispensable · waivable · at-will · negotiable · flexible · choosable
contingent
Conditional or representative group
- circumstantialBased on inference, not proof
- provisionalConditional and possibly temporary
- dependentRequiring outside support
situational · qualified · prerequisite · stipulation · proviso · hypothetical · eventuality · precondition · variable
anaerobe
Organism needing no oxygen
- parasiteOne exploiting a host
- symbiontOrganism sharing mutual benefit
- mutualistPartner in mutual benefit
pathogen · saprophyte · heterotroph · organism · adaptation · metabolism · survival · opportunistic · commensal · ecology
dispensation
Official permission to skip rules
permission · papal · bishop · clergy · authority · exemption · ecclesiastical · delegation
- microbiologybacteria, bacterium, microbe, microbes, microorganisms
- Microbesbacteria, bacterium, virus, mold, prokaryote
- Reinsurancereinsurer, retrocession, retention, cession, proportional
- insuranceinsurance, coverage, auto insurance, life insurance, home insurance
- bacteriaE. coli, Clostridium, Salmonella, salmonella, Pseudomonas
- symbiosissymbiosis, mycorrhizae, symbiont, symbiotic, mutualism
facultativeobligatory
Required by rule
compulsory · obligate · mandatory · required · necessary
facultativeobligate
Commit by necessity
obligatory · strict · constitutive · permanent · fixed
facultativedisabling
Causing loss of function
disqualifying · prohibitive · restrictive · incapacitating · preclusive