Intelligibility is how easy it is to understand speech, writing, or an idea. If a recording has high intelligibility, you can catch the words even when there is noise. If a text has low intelligibility, you see the sentences but cannot hold the meaning. People who teach speaking, and people who make phones and hearing machines, use this word a lot. It is a little technical. In ordinary talk most people just say “I can understand it” or “it is clear.” It is not the same as intelligence, which is about being clever. A clever talk can still have poor intelligibility if the speaker does not open their mouth enough.

可懂度、可理解性（語言學與語音裡常用「可懂度」，指聽不聽得懂、清不清楚）