Can cards that negate/reduce battle damage be used against direct damage?

I recently started using a Watt deck, and in a recent duel, an opponent tried to use Kuriboh when I attacked with Wattgiraffe. Wattgiraffe can attack the opponent directly, and Kuriboh can reduce the battle damage of 1 monster by 0 by discarding it. Can a card that only says "battle damage" on it be used to negate/affect damage done directly by a monster?