Definitions of device
a mechanical or electronic object that has been made for a particular purpose
Snoopers can tap in to telephone conversations using a simple device available in shops for less than £100.
a plan, method or trick with a particular purpose
The sterling money market in London is the device used by banks to adjust their liquidity.
If you leave someone to their own devices then you leave them alone to do what they want.
He left her to her own devices.