If you're on the hunt for an outstanding Halloween costume that starts with the letter "O", look no further! This list overflows with options, from nostalgic characters to over-the-top personas that will make you the talk of the party. Whether you're aiming for outrageous fun or opting for something a bit ominous, we've got you covered with these original ideas. Let's dive into these out-of-this-world costumes!
1. Oogie Boogie Costume
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Channel the boogeyman himself with an Oogie Boogie costume. As the villain from The Nightmare Before Christmas, Oogie embodies creepy fun. With his iconic burlap look and ominous song, you'll have everyone singing "What have we here?" as you show up to the Halloween bash!
2. Oompa Loompa Costume
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Transport yourself to the world of Willy Wonka with a classic Oompa Loompa costume. These orange-skinned, green-haired factory workers are not only memorable but also perfect for a group costume. With a catchy tune on your lips, you'll have people humming "Oompa Loompa, doompety doo" all night long!
3. Old Lady Costume
Give your Halloween look a transformative twist by dressing up as an old lady. This costume is simple to pull together but full of personality. With some accessories like a granny wig, oversized glasses, and maybe a walker, you'll be on your way to enjoying a delightful evening filled with jokes about forgetting your candy.
4. Optimus Prime Costume
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Transform your Halloween with an Optimus Prime costume! The heroic leader of the Autobots is a towering force of justice. With his catchphrase, "Autobots, roll out!" leading the way, you'll be ready to protect the world—or at least the party—from Decepticons.
5. Olaf Costume
Warm up this spooky season as Olaf, the lovable snowman from Frozen. His cheerful "I like warm hugs" mantra will make you the friendliest figure at any Halloween event. An Olaf costume is both cute and cozy, perfect for bringing some frosty fun to your festivities.
6. Oscar the Grouch Costume
Infant Oscar the Grouch Costume
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Be everyone's favorite cranky Muppet with an Oscar the Grouch costume. Straight from Sesame Street, Oscar may live in a trash can, but his sarcastic attitude and grumpy charm will bring plenty of laughs. Just remember to tell everyone, "Scram! I love trash!"
7. Old Man Costume
Embrace your inner senior citizen with an old man costume. Whether you go for the grumpy grandpa or the sweet, candy-giving elder, this costume is simple yet hilarious. Add a cane and some funny complaints about "kids these days," and you'll be the life of the party.
8. Octopus Costume
Make a splash at your Halloween event with an octopus costume! With tentacles galore, you'll be hard to miss. Whether you opt for a cute or slightly creepy version, this underwater creature is bound to reel in the compliments.
9. Olive Oyl Costume
Straight from the classic Popeye cartoons, an Olive Oyl costume is perfect for a retro look. Olive's iconic hairstyle and quirky personality make this a fun, easy option. Pair it with a Popeye or Bluto for a fantastic couples costume!
10. Orca Costume
Dive into the ocean's depths with an orca costume. Known for their majestic black-and-white appearance, orcas bring a striking presence to any event. Glide through the party like the "killer" whale you are!
11. Otter Costume
Add a dash of cuteness to Halloween with an otter costume. Known for their playful nature, otters are an adorable costume choice. You'll be as cute as an otter cracking open some candy instead of clams.
12. Oreo Costume
Satisfy everyone's sweet tooth with an Oreo costume! This cookie costume will surely be a hit, but beware of anyone looking to dunk you in milk!
13. Onion Costume
Spice up Halloween with an onion costume! This veggie-inspired outfit will get a few laughs and maybe even a tear or two. Just remind people that, like onions, your costume has many layers!
14. Orangutan Costume
Bring the jungle to Halloween with an orangutan costume. Known for their intelligence and playful nature, dressing as an orangutan will give you the perfect excuse to swing into some mischief. Get ready for a night of monkeying around!
15. Obi-Wan Kenobi Costume
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Become the legendary Jedi with an Obi-Wan Kenobi costume. This wise and powerful character from Star Wars is instantly recognizable with his robes and lightsaber. Don't forget to remind everyone, "The Force will be with you, always."
16. Oaken Costume
Bring the warmth of a cozy trading post to Halloween with an Oaken costume. From Frozen, this lovable shopkeeper is best known for his cheery "Yoo-hoo! Big summer blowout!" line. Keep the good vibes going as you welcome everyone with a smile.
17. Winnie the Pooh Owl Costume
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Take flight as the wise and talkative Owl from Winnie the Pooh. Known for his long-winded stories and love for giving advice, Owl is an excellent choice for those who enjoy a classic costume. Let your wisdom soar as you tell tales at the party.
18. Sandy Olsson Costume
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Recreate the magic of Grease with a Sandy Olsson costume! Whether you choose the sweet, girl-next-door look or Sandy's bold transformation in her leather jacket, you'll be the one that everyone wants. Get ready to rock the night with some serious '50s flair.
19. Oliver Queen Costume
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Step into the shoes of the Green Arrow with an Oliver Queen costume. As the skilled archer and vigilante, you'll exude confidence and style. Armed with your bow and arrow, you're ready to take down the bad guys—and maybe win a costume contest or two.
20. Opossum Costume
Be a little unconventional this Halloween with an opossum costume. These nocturnal creatures are known for playing dead, so you can take plenty of dramatic naps between trick-or-treating sessions. Embrace the unexpected with this quirky animal disguise.
21. O-Ren Ishii Costume
Channel your inner warrior as O-Ren Ishii from Kill Bill. With her katana and sleek style, this fierce assassin makes for an eye-catching costume. Just remember: revenge is a dish best served cold.
22. White Owl Costume
Embody the mystery of the night with an owl costume. These majestic birds of prey are symbols of wisdom and are often associated with Halloween. Glide through the party silently, keeping an eye out for fun and maybe a few spooky surprises.
We hope these outstanding "O" costumes have sparked some exciting ideas for your Halloween! If we missed any of your favorite "O" costumes, feel free to leave a comment or drop us a suggestion. We'd love to hear how you're planning to make this Halloween an outstanding one!
You can also feel free to check out our other costumes by letter.
