a derogatory term的用法和样例：
- The word `pig' is a derogatory term for policeman.
- Good-for-nothing(a derogatory term for someone who is lazy or irresponsible).
- This is a derogatory term for someone who is intelligent yet socially awkward.
- In Chinese class, the teacher shows the students how to use a derogatory term to convey a positive meaning.
- Widely spread, though, liberalism was mainly used as a derogatory term by the Russians.