n.[C]

1. 骑马（或骑脚踏车等的）人；搭乘的人
2. （文件后面的）附文；（议案的）附加条款
   I only wanted to add one little rider to what you were saying.

   我只是想对你说的附加一点意见。

3. （机件等）架在上面的套件，叠件

n.

1. a person who rides a horse, bicycle, motorcycle, etc.
2. an added condition or proviso.
   ▸Brit. an addition or amendment to a bill at its third reading.
   ▸Brit. a recommendation or comment added by the jury to a judicial verdict.
   ▸food, drink, etc. provided for a performer as specified by a clause in their contract.
3. a small weight on the beam of a balance for fine adjustment.