* Idiom: A phrase or expression that has a figurative meaning, often different from the literal meaning of its individual words. They are commonly used and understood within a particular language or culture. Examples include "kick the bucket" (meaning to die) or "raining cats and dogs" (meaning raining heavily).
* Slang: Informal language considered peculiar to a particular group of people, typically used in place of standard terms. Slang is often short-lived and can vary greatly between groups. Examples include "chill" (meaning to relax), "bae" (meaning sweetheart), or "lit" (meaning exciting or amazing).
Here's a key difference:
* Idioms are often part of the standard language, while slang is usually considered outside of it.
* Idioms are often figurative, while slang can be literal.
Therefore, while some idioms may be considered informal, they are not technically slang words.