vt.

1. 使从座位上（或马背上）摔下
   The horse kicked and reared, unseating its rider.

   马猛踢一下用后腿站立，将骑马人摔了下来。

2. 剥夺……的席位；使下台（或退职，退位）
   The opposition tried to unseat the government.

   反对党试图推翻政府。

v.

1. cause to fall from a saddle or seat.
2. remove from a position of power or authority.