n.

1. 计算[U]
   Did I make any error in my calculation?

   我计算中有没有出差错？

2. 计算结果[C]
   The scientist's calculations proved exactly right.

   那位科学家的计算结果完全正确。

3. 估计，推测，预测[U][C]
   By my calculation, 5% of the students will fail in the exam.

   据我估计，百分之五的学生不能通过这次考试。

4. 深思熟虑；盘算[U]
   After much calculation they decided to give him the position of manager.

   经仔细考虑，他们决定让他担任经理职务。

n.

1. a mathematical determination of quantity or extent.
2. an assessment of the risks or effects of a course of action.