An idiom is a phrase or expression that has a figurative meaning that is different from the literal meaning of the words.
For example:
* "Kick the bucket" literally means to kick a bucket, but figuratively it means to die.
* "Break a leg" literally means to injure your leg, but figuratively it means "good luck."
Therefore, the literal meaning of an idiom is not particularly useful in understanding its actual meaning. You need to understand the figurative meaning to understand what the idiom is trying to convey.