n.[C]

1. 机械装置；机械作用
   An airplane engine is a complex mechanism.

   飞机引擎是种复杂的机械装置。

2. 机构；结构
   The mechanism of local government is far from perfect.

   地方政府的结构还很不完善。

3. （自然现象产生的）物理过程；【化】历程；【生】机制
   Meteorologists believe this pressure jump is the mechanism responsible for storms and tornadoes.

   气象学家认为这一气压的突然升高是暴风雨和飓风形成的物理机制。

4. 办法，途径
   There's no mechanism for changing the decision.

   没有办法改变这一决定。

5. （绘画等的）手法，技巧
   The three sisters were all well-versed in the mechanism of novel writing.

   三姐妹都熟谙写小说的技巧。

n.

1. a piece of machinery.
2. a process by which something takes place or is brought about.
3. Philosophy  the doctrine that all natural phenomena allow mechanical explanation by physics and chemistry.