What part of speech is sigh?

"Sigh" can be a few different parts of speech depending on how it's used:

* Noun: When referring to the act of sighing itself.

* Example: "He let out a deep sigh."

* Verb: When describing the action of sighing.

* Example: "She sighed with relief."

* Interjection: When used to express a feeling or emotion, often sadness or disappointment.

* Example: "Sigh, I wish I could go."

So, without context, it's impossible to definitively say what part of speech "sigh" is.