An idiom is an expression common to a particular culture that does not mean what it literally says. For example, "to rain cats and dogs", which means "to rain very heavily", is an idiom. "Break a leg!", which means "good luck!", is another one.
A proverb is a short popular saying that gives advice about how people should behave or that expresses a belief that is generally thought to be true. Here are some examples:
- Don’t cry over spilled milk.
- All is fair in love and war.
- A friend in need is a friend indeed.
Like idioms, proverbs often have a meaning that is greater than the meaning of the individual words put together, but in a different way than idioms. The literal meaning of an idiom usually doesn’t make sense, and idioms can be almost impossible to understand unless you have learned or heard them before.
However, the literal meaning of a proverb such as “Don’t cry over spilt milk” does makes sense on its own, but it’s not until you apply this meaning to a real situation that you understand the real point of the proverb. For example, “Don’t cry over spilled milk” means “Don’t get upset over something that has already been done. It’s too late to worry about it now, just get on with your life”.