* Noun: This is the most common usage. It refers to the act of convincing someone to do something or believe something.
* Verb: This is less common, but it's possible to use "persuasion" as a verb meaning "to persuade." This is usually more formal and literary.
* Adjective: This is also less common, but "persuasive" is a common adjective meaning "having the power to persuade."
Examples:
* Noun: The lawyer used persuasion to convince the jury.
* Verb: He persuaded me to go to the party.
* Adjective: She gave a persuasive speech about the importance of voting.
So, without context, it's hard to say for sure what part of speech "persuasion" is. You need to look at the sentence it's used in.