A condition that must be satisfied for a result or proposition to hold; necessary but not necessarily sufficient on its own.
合格するための必要条件は受験料を払うことだが、それだけで合格は保証されない。
A necessary condition for passing the exam is paying the exam fee, but that alone doesn't guarantee passing.
酸素の存在は生命維持の必要条件の一つだ。
The presence of oxygen is one of the necessary conditions for sustaining life.
論理学では、必要条件と十分条件を区別して考える。
In logic one distinguishes between necessary conditions and sufficient conditions.