Redundant means more than what's needed, often unnecessarily repetitive or no longer necessary. When something is redundant, it serves no additional purpose because you already have what it provides.

In writing, redundant phrases waste words by saying the same thing twice. “Free gift” is redundant because gifts are always free. “Added bonus” is redundant because a bonus is something extra by definition. When your teacher asks you to cut redundant words from your essay, she wants you to remove repetition that doesn't add new information.

In engineering and safety systems, redundancy can be valuable: a spacecraft might have redundant backup computers in case one fails. But in most everyday situations, redundant means wastefully repetitive.

The word also describes something that's been made obsolete or unnecessary. When a new invention makes an older tool redundant, people stop needing the old one. Email made many paper memos redundant in offices. When companies eliminate redundant positions, they're removing jobs that duplicate work being done elsewhere.

If you're explaining something and your friend says “you're being redundant,” they mean you're repeating yourself unnecessarily. The goal is to say what you need once, clearly, without circling back to repeat the same point over and over again.