What is similies words of A clown is as funny as a
Similes compare two things. Because clowns are considered by most to be very funny, the object would also have to be something funny. Therefore you could say... A clown is as funny as a medieval joker. A clown is as funny as a cat barking like a dog. A clown is as funny as a comedy movie.
a similes for that is A clown is as funny as my sister falling or a clown is a funny as a dog barking you really have no wrong answer with that