facultative

• 形容词，指非强制的、可选的；在生物学中特指能在多种环境条件下生存或适应的（如兼性厌氧菌）。

An adjective meaning optional or not compulsory; also used in biology to describe an organism capable of adapting to different conditions.

1. Relating to mental facultiesC2formal

   Pertaining to the inherent powers of the mind, such as reason, memory, or will.

   与心智能力有关的

   • The philosopher examined the facultative operations of the human intellect.
   • Meditation can enhance certain facultative abilities like focus and recollection.
   • Brain injury sometimes impairs facultative functions such as decision‑making.

2. Capable of adapting to different conditionsC1formalscientific

   Able to exist, grow, or function under more than one set of environmental or physiological circumstances.

   兼性的

   • This bacterium is facultative, thriving both with and without oxygen.
   • Many plants display facultative responses to changes in light intensity.
   • The organism’s facultative nature helps it survive in fluctuating habitats.

   同义词adaptableflexibleversatile

   反义词obligate

3. Conferring permission or optionC2formallegal

   Granting a privilege, authority, or liberty to choose to do or not to do something.

   选择性的

   • The treaty included a facultative clause allowing member states to opt out of certain obligations.
   • A facultative mandate gives the representative discretion to act as they see fit.
   • Under facultative provisions, the company may but is not required to renew the contract.

   同义词discretionaryelectiveoptionalpermissivevoluntary

   反义词compulsorymandatoryobligatoryrequired

4. Not compulsoryB2formal

   Optional; left to individual choice rather than being required or mandatory.

   非强制性的

   • Attendance at the seminar is facultative for all students.
   • The course includes facultative modules that students can select based on interest.
   • Payment of the membership fee is entirely facultative.

   同义词discretionaryelectivenonmandatorynonobligatoryoptionalvoluntary

   反义词bindingcompulsorymandatoryobligatoryrequired