A patent is an official legal right that protects an inventor's creation, preventing others from making, using, or selling that invention without permission. When someone invents something new and useful, like a better mousetrap or a new kind of battery, they can apply to the government for a patent. If approved, the patent gives them exclusive rights to their invention for a set period of time, usually twenty years.

Think of a patent as a temporary monopoly granted as a reward for innovation. Thomas Edison held patents for the light bulb and the phonograph. The Wright Brothers patented their airplane design. More recently, inventors have patented everything from smartphone features to new medicines. Without patents, anyone could copy a new invention the moment it appeared, which would discourage people from spending years developing new ideas.

To get a patent, inventors must publicly explain exactly how their invention works. This creates a trade: the inventor gets protection for a limited time, but eventually the knowledge becomes available for everyone to use and improve upon. That's why medicines eventually become cheaper generic versions after their patents expire.

The word patent can also work as an adjective meaning obvious or clear, though you'll encounter this usage less often. When something is patently false, it's obviously and unmistakably wrong.