To instruct means to teach someone how to do something or to give them clear directions about what to do. When your teacher instructs the class on long division, she's showing you the steps and explaining how they work. When a coach instructs players on a new play, he's telling them exactly where to stand and what to do.

The word emphasizes clarity and authority. An instructor doesn't just suggest or hint; they provide direct, specific guidance. A recipe instructs you to preheat the oven to 350 degrees, not “maybe make it sort of warm.” A lifeguard instructs swimmers to stay in the shallow end, using clear words that leave no doubt about the rules.

You'll often see related words: an instructor is someone whose job involves teaching, like a swimming instructor or karate instructor. Instructions are the step-by-step directions themselves, whether you're following instructions to build a model airplane or reading the instructions for a board game. Being instructed means receiving teaching or orders: “The students were instructed to work quietly.”

The key difference between instructing and just telling someone something? Instructing is purposeful and organized, designed to help someone learn a skill or understand how to do something correctly.