Is the word this a demonstrative pronoun?

Yes, "this" is a demonstrative pronoun when it stands alone and refers to a noun that is understood from the context.

Here are some examples:

* "This is my favorite book." Here, "this" refers to a book that is understood from the context.

* "I like this one better." Here, "this" refers to an object that is understood from the context.

However, "this" can also be a demonstrative adjective when it modifies a noun.

For example:

* "This book is my favorite." Here, "this" modifies the noun "book."

So, the word "this" can be both a demonstrative pronoun and a demonstrative adjective depending on its function in the sentence.