Definitions: Overloading

Overloaded pieces can be difficult to spot, sometimes it's a fine line between a piece operating energetically and it becoming overworked. The overloaded piece will usually be somewhat immobilised by it's juggling act.

Overloading: Applying pressure to a piece that is performing two or more simultaneous defensive tasks.

Reinfeld Position #426
White to move

The Black Queen is overloaded defending the Queen + Rook + Knight barrage against g7, while also defending the weak back rank at c8. White uses the second threat to decoy the queen away from defending the first.
1. Rc8+ Qxc8 2. Qxg7+ Rxg7 3. Rxg7#