What part of speech is the word seen?

The word "seen" can be a few different parts of speech, depending on how it's used in a sentence:

* Past participle of the verb "to see": This is the most common usage. For example: "I have seen the movie."

* Adjective: It can be used as an adjective to describe something that is visible. For example: "The seen world."

* Part of a phrasal verb: It can be part of a phrasal verb, like "see through". For example: "He saw through her lies."

To determine the specific part of speech, you need to look at its context in the sentence.