entirely
Completely, with no parts left out or unfinished.
Entirely means completely, totally, or in every way possible. When something is entirely finished, there's nothing left to do. When you've entirely cleaned your room, every corner is spotless and every item is put away.
The word emphasizes that there are no exceptions or partial measures. If you entirely agree with someone, you agree with every single point they're making. If a cake is entirely chocolate, it's chocolate through and through, from the batter to the frosting.
You'll often see entirely used to strengthen statements. A teacher might say that failing a test wasn't entirely your fault if you were sick that week, meaning other factors played a role. When someone says “That's an entirely different question,” they're emphasizing that the new question is completely separate from what was being discussed.