Definition of "Device" :
noun: any clever maneuver
"He would stoop to any device to win a point."
noun: an instrumentality invented for a particular purpose
"The device is small enough to wear on your wrist."
noun: an emblematic design (especially in heraldry)
"He was recognized by the device on his shield."
noun: any ornamental pattern or design (as in embroidery)
noun: something in an artistic work designed to achieve a particular effect