To mispronounce a word means to say it incorrectly, getting the sounds wrong in a way that makes it hard for others to understand what you mean, or that sounds odd to people who know the proper way to say it. When someone mispronounces “library” as “lie-berry” or “nuclear” as “new-cue-ler,” they're saying the word differently from its accepted pronunciation.

Mispronouncing words happens to everyone, especially with words we've only seen written down but never heard spoken aloud. You might read about ancient “pharaohs” in a book and guess it's pronounced “FAR-ohs,” when it's actually “FAIR-ohs.” Scientists and doctors regularly encounter colleagues who mispronounce technical terms they've only read in research papers.

The tricky part about mispronunciation (the noun form) is that it can make communication harder, but it can also be a sign that someone reads a lot and learns new words from books. Many successful people tell stories about mispronouncing sophisticated words they taught themselves through reading. What matters is being willing to learn the correct pronunciation when someone kindly points it out, rather than feeling embarrassed. Even expert readers have mispronounced dozens of words along the way.