Anode

The anode is the electrode in an electrochemical cell, be it a battery, electrolytic cell, or vacuum tube, where oxidation occurs. 

It's conventionally defined as the electrode from which current flows out of the cell into the external circuit. For a galvanic (voltaic) cell (like a battery providing power), the anode is the negative terminal. Electrons are released here as the anode material is oxidized. Conversely, for an electrolytic cell (like during charging), the anode is the positive terminal, as it's connected to the positive terminal of the external powersource.