Orange
^^ Well done.
btw I already have:
Ororo
Olive Oyl
Oompa loompa
Officer
Olivia from Family Guy
Olivia Newton John as Sandy
for those who want to contribute a good answer.
Costume ideas that begin with the letter i:Incredible HulkIndianIndiana JonesInmate
ambulance attendantastronautanimal
trendy
· Ballerina · Barbie · Bo Peep
angel alice:twilight braham Linchom
Skeletor costume starts with s.
Red Riding Hood rabbit (an Easter Bunny costume comes to mind) robot race car driver
You could dress as the grim reaper, a golfer, gypsy or a gangster.
Halloween Costume Ideas for Men Women and Kids. Pumpkin carving tips, Safety tips, Sexy couples Ideas, Halloween Foods http://halloween-costume-ideas-2013.blogspot.com/
Nun Ninja Ned Kelly Nurse Nerd Netball player Neuro-surgeon
You could dress as Uncle Sam or an umpire. They begin with the letter u.
http://www.halloween.com/halloween-costume-quick-ideas.php