calculus

/ˈkælkjələs/

a hard lump produced by the concretion of mineral salts; found in hollow organs or ducts of the body

中文释义：结石；微积分

The patient was diagnosed with a kidney calculus and needed surgery.

该患者被诊断出肾结石，需要手术。

Calculus is a fundamental course for students majoring in physics.

微积分是物理专业学生的基础课程。