bide one's time meaning

[American idiom]
to wait patiently.
• I've been biding my time for years, just waiting for a chance like this.
• He's not the type just to sit there and bide his time. He wants some action.

[American slang]
to wait patiently.
  I've been biding my time for years, just waiting for a chance like this.
  He's not the type just to sit there and bide his time. He wants some action now.