You are in the right place if you are looking for O theme dress up ideas, we have come up with a whole list of costume suggestions, admittedly some are more obscure than others but that is half the fun when you have only been given a single letter to work with. Take a look through this page at our ideas for costumes starting with the letter O.
Ogre – Shrek and Fiona complete with green face paint are perfect ogres.
Opera Singer – One of our Medieval dresses with a Viking helmet would work well for this.
Oz – Mayor from the Wizard of Oz