1. To issue a verbal or written answer or reply to someone or something. I spent my entire first day back from vacation just responding to emails that had been piling up. Mary is obviously still angry—she won't even respond to me.

2. To act in response or in answer to someone or something. There are a number of ways we can respond to this injunction. My father believes you have to respond to a bully with force.

3. To elicit a reaction, especially a positive one, to a particular person or stimulus. We're pleased to see that your body has been responding to the new treatment methods. Our baby daughter doesn't really like to be held by most people, but she really responds to my mother-in-law.