The suffix -ible attaches to the end of words to mean “able to be” or “capable of being.” When you see a word ending in -ible, you're looking at something that can have an action done to it.

If something is visible, it can be seen. If food is edible, it can be eaten safely. A reversible jacket can be turned inside out and worn either way. When a sound is barely audible, you can just barely hear it.

English has a similar suffix, -able, which often works the same way but usually attaches to complete English words or French-derived roots. Both suffixes do the job of creating adjectives that describe potential or capability. While there aren't strict rules for when to use which one, -ible words tend to look and feel more formal: compare collectible with comfortable.

When you encounter a new -ible word, you can try removing the suffix and thinking about the root. What action could be done? That can be the key to understanding what the word means.