Definition of:power adapter
power adapter

A power supply for just about every electronic device on the market. Also called an "AC adapter" or a "charger" if used to recharge a battery, it plugs into the wall and converts AC current to a single DC voltage in most cases. There are also adapters that output a different AC voltage. Laptops have both an external power adapter, also called a "power brick," and an internal power supply. If an external power adapter is not used with an electronic product such as a desktop computer, the DC current is created in a power supply inside the unit. See transformer, power supply, power distribution unit, power strip and USB charger.

The Power "Brick"
Used with laptops and other electronic equipment, the external power adapter converts AC to a single DC voltage, and the laptop's internal power supply converts the DC to several different DC voltages. Although the power adapter is never included in the advertised weight of a laptop, most everyone keeps it in their laptop cases when they travel any distance.

The "Wall Wart" Adapter
The little black power adapter with its own wall plug is found with most every small electronic product. Dubbed "wall warts," they overlap into adjacent sockets, and many power strips add extra space to accommodate them.