disconnect
Concise Oxford English Dictionary © 2008 Oxford University Press:
disconnect/dɪskəˈnekt/
▶verb break the connection of or between.
■ put (an electrical device) out of action by detaching it from a power supply.
▶noun an instance of disconnecting or being disconnected.– derivatives
disconnection (also disconnexion) noun.
disconnection (also disconnexion) noun.
'disconnect' also found in these Oxford entries:

