Function
Part of speech: verb
Definition: to have a function to carry on a function; to be in action
Part of speech: noun
Definition: What something does or is used for. A professional or official position. An official or social occasion. A relation where one thing is dependent on another for its existence, value, or significance. A relation in which each element of the domain is associated with exactly one element of the codomain. A routine that receives zero or more arguments and may return a result. The physiological activity of an organ or body part. The characteristic behavior of a chemical compound.
Example sentence: Criticism may not be agreeable, but it is necessary. It fulfils the same function as pain in the human body. It calls attention to an unhealthy state of things.
Use
Part of speech: noun
Definition: The act of using.Usefulness, benefit.A function; a purpose for which something may be employed.
Part of speech: verb
Definition: To accustom; to habituate.To employ; to apply; to utilize.To exhaust the supply of; to consume by employingTo exploit.To be accustomed.
Example sentence: Intelligence is what you use when you don't know what to do: when neither innateness nor learning has prepared you for the particular situation.