What does the word “nope” mean?

Definition: no.

Example: “Are you coming to the mall with us?” —”Nope. Got too much homework to do.”

Note: “Nope” may be used in place of “no” when all three of these conditions are met:

1) “Nope” is by itself—you can’t use it in a phrase.
2) The conversation is extremely informal. The word isn’t written, except in dialogue.
3) You’re answering a question or responding to a positive statement.