What part of speech is the word will?

"Will" can be a few different parts of speech, depending on its function in a sentence:

* Modal Verb: This is the most common use of "will." It indicates future tense or willingness, and is followed by a verb in its base form.

* Example: "I will go to the store later."

* Noun: It can refer to a document that expresses a person's wishes for the distribution of their property after death.

* Example: "She signed her will last week."

* Verb: "Will" can also be a verb meaning to desire or be determined to do something.

* Example: "I will to succeed."

To determine which part of speech "will" is, you need to look at its role in the sentence.