Verb: To frustrate means to make someone feel annoyed or discouraged because they are unable to achieve something.
* Example: "The constant traffic frustrated me."
Adjective: Frustrated means feeling annoyed or discouraged because of an inability to achieve something.
* Example: "I felt frustrated after failing the exam."
There is no noun form of "frustrate" in common usage. You might use the noun "frustration" to describe the feeling or state of being frustrated.