1unit (of measure)
2unit (group of people as a whole)
3work unit (place of employment, esp. in the PRC prior to economic reform)
Examples
nǐ你wèi shén me为什么huì会chū xiàn出现zài在wǒ我gōng zuò工作dān wèi单位？
你为什么会出现在我工作单位？
Why would you appear in my unit?
在我的单位，我是最年轻的。
I'm the youngest in my department.
我有时候走路去上班，有时候骑自行车去上班，因为我家离单位很近。
Sometimes I walk to work, and sometimes I ride my bike, because I live very close to work.