on one's own time meaning

[American idiom]
not while one is at work.
• The boss made me write the report on my own time. That's not fair.
• Please make your personal telephone calls on your own time.

[American slang]
not while one is at work.
  The boss made me write the report on my own time. That's not fair.
  Please make your personal telephone calls on your own time.

• in one's own time:    In one's spare tim ...
• a legend in one's own (life)time:    [American slang]Fi ...
• not able to call one's time one's own:    [American idiom]to ...