Augustus Ceasar
Someone could dress as an umpire. The costume begins with the letter U.
Widow
teddy bear
You can dress as Tarzan or a tramp. You can dress as Tony the Tiger or the Tin Man.
Scooby doo, spongebob, or Superman
Jailbird, janitor, Jedi, jockey, the Joker, judge and Julius Caesar are dress up ideas.
You can dress as E.T. You can dress as Elvis Presley. You can dress as an elephant.
LanaGames
Animal
Unicorn, Umbrella
That ... they should dress up as santa.
You can dress as King Neptune, a king, kitten or a knight.