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responder

American  
[ri-spon-der] / rɪˈspɒn dər /

noun

  1. a person or thing that responds.

  2. Electronics. the part of a transponder that transmits the reply.


Etymology

Origin of responder

First recorded in 1875–80; respond + -er 1

Explanation

A responder is someone who answers a question or who acts quickly in response to some event. If there's only one responder to all of your teacher's questions, he'll start calling on other students to answer as well. Anyone who responds, or reacts, in some way is a responder, whether their responses are spoken, sung, or acted out physically. You're likely to find this word in the context of "first responders," a term that's used for police officers, firefighters, EMTs, or anyone else whose job puts them among the people who help in an emergency or disaster.

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

A responder from the air ambulance was also in attendance.

From BBC • Jun. 4, 2026

An emergency responder started to perform CPR on Bautista, who was soon transported to a medical center.

From The Wall Street Journal • May 28, 2026

When I was in Iraq, on patrol and during emergency responder training, I was given the option of picking my own radio call sign.

From Slate • Apr. 13, 2026

His grandson Mendy Amzalak told The Australian that he had rushed to the scene on the beach as a first responder.

From Barron's • Dec. 17, 2025

I was taking a certified first responder course with the lifeguards.

From "Adrift" by Paul Griffin

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