It's pronounced gah-jit, slang for any hardware device, usually small. Smartphones, tablets, and portable game and music players are sometimes placed in the device category. A device is a tool or device, especially one that works great for a specific task. Your father's favorite kitchen utensil could be his special knife that cuts vegetables in spirals.
In 1983, the animated television series Inspector Gadget introduced the iconic and clumsy detective with several bionic devices embedded in his body. Where the first gives the word gadget the meaning of a sailor slang word for any small mechanical thing or part of a ship, while the second states that the word was used to name any piece of mechanism, the name of cannot be remembered. The remote control that your brother places on the Christmas tree is a gadget, and your camping tool that unfolds on various knives, corkscrews and scissors is another type of device.