Donkey Kong is not a donkey. He is a gorilla. He was named Donkey Kong so he would appear less frightning. Apes can be frightning. Donkeys, not really.
Shigeru Miyamoto, the character's creator, used the English word "donkey" to evoke the animal's stereotypical stubbornness. (There was no translation error; the game has the same name, "Donkii...