At Work Meaning

(idiomatic) Working, in the process of doing work.

Example: At one's workplace.
  He's not at home at the moment, he's at work.
  They've got a new photocopier at work. (At my workplace, they have a new photocopier.)
During customary work time.
  Don't call me at work.
  Don't interrupt me while I'm at work on my housing project.