It is the first person singular present tense of the verb "devolver", which means "to return" or "to give back".
Here are some examples of how "devuelvo" can be used:
* "Te devuelvo el libro" - I return the book to you.
* "Devuelvo el dinero que me prestaste" - I give back the money you lent me.
* "No devuelvo las llamadas" - I don't return calls.
Note: The pronunciation of "devuelvo" is deh-vwayl-voh.