The clinical term for the extreme fear of clowns is coulrophobia.
Mr. Clown: Happy birthday, nice puppy boy.
Wakko: Clown! (slams the door in the clown's face)
Mr. Clown: That hurt my face.
Mr. Clown: (singing) When the Whippoorwill / Whippers in the wind / The wind can whipper back...
Martian Kids: Oh, nice and chubby, baby!
Mr. Clown: I like it here!
Wakko: Bye-bye, Mr. Clown!
Mr. Clown: Freungugenlevenschild!!
Mr. Clown: Hey, little birthday boy! I got my little clown car! Froylaven! Froylaven!
Mr. Clown: A puppy! Hello, I'm a puppy, barklevenwoof!
Mr. Plotz: ...A clown is my friend.
Dr. Scratchansniff: A clown will not bite me und throw me in the basement.
Mr. Plotz: A clown will not bite me and throw me in the basement.
Dr. Scratchansniff: A clown is not a big schpider.
Mr. Plotz: A clown is not a big spider.
Mr.Plotz: Now, I--I'm well aware that Wakko can be extremely difficult at times; nevertheless, it is his birthday today, so I want you to go on up to the water tower and surprise him. Do your little birthday show-skit thing.
Mr. Clown: Oh! For the boy? Make a surprise? I just love makin' a surprise!
Mr. Plotz: I-I-I-ah-I want you to go away now. You frighten me!
Mr. Clown: You shouldn't be frightened of me, Mr. Man. I'm just a clown. Freungoldenlevenscheuld!
Mr. Plotz: Yaaaaaagh!! Please, please, I'm begging you! Get out, go!
Mr. Clown: Oh, poor Mr. Man. (singing) When you want to scream / Put away that frown / And never be scared of a clown! / Laugh on, laugh on, laugh on and on and on, / You'll never laugh alone!
Mr. Plotz: OUT, CLOWN!