intelligibility

Intelligibility describes the quality of being clear enough to be understood, especially in speech or sound. It is not only about whether words are spoken, but about whether a listener can recognize them easily and correctly. A sentence can be loud enough to hear and still have poor intelligibility if the speaker mumbles, the recording is distorted, or there is too much background noise.

This word is used most often in areas connected to listening and speaking. In speech therapy, teachers and clinicians may talk about a child's speech intelligibility to describe how easily other people can understand them. In audiology and hearing studies, intelligibility helps describe how well a listener can make out spoken words. In audio engineering, people care about intelligibility when setting up microphones, phones, recordings, radios, or public address systems, because the goal is not just volume but clear words.

The idea can also be used more broadly for language that is easy or hard to follow, but its strongest and most common use is with spoken communication. For example, a witness may speak quietly, an announcer may be masked by crowd noise, or a synthetic voice may sound smooth but still have low intelligibility if listeners miss the words. In every case, the core idea is the same: how easy it is for a person to understand what is being said.