To describe something means to use words to paint a picture of it in someone else's mind. When you describe your new puppy to a friend, you might explain that she's small and fluffy, with one brown ear and one white ear, and that she loves to chase her tail. When a witness describes a suspect to the police, they explain what the person looked like, what they were wearing, and how they behaved.

Good descriptions use specific details that help others see, hear, or feel what you're talking about. Saying “the weather was bad” is vague, but saying “rain pounded against the windows while wind howled through the trees” lets readers practically feel the storm. Scientists describe their experiments carefully so others can understand and repeat their work. Authors describe settings and characters to bring stories to life.

The noun form is description. When someone asks for a description of an event, they want the details: what happened, when, where, and how. Police might circulate a description of a missing person. A job description explains what tasks someone in that job performs.