socket wrench
A wrench that use specifically shaped holes on their ends (usually a hexagon or square), called sockets, that allowed the wrench to turn many bolts, nuts, and other fasteners of different sizes and shapes.
The sockets can be on separate metal pieces that can attached to the wrench, making it interchangeable with other sockets, or are physically fixed to the wrench. The wrenches can either features a reversible ratcheting mechanism or not, which allows the user to pivot the tool back and forth to turn its socket instead of removing and repositioning the wrench to do so, during its usage in enclosed space. hence the reason why some of them are referred as ratchets.
This tag also applies to any tools for the similar purpose (like a breaker bar), or any specific kinds of socket wrenches.