IOO 

In Our Opinion. The plural form of IMO.

"Is Allan the best dressed man in the world?"

"Yes, IOO"

IOO by SexyJosem July 21, 2012

ioo 

I don't know.

Instant messaging slang. Usually follows a question.

<Chris> What time do you want to leave?
<Tim> ioo

ioo by Johnno31 August 7, 2006

IOO 

Used to define "One Hundred" in Roblox since no-one can type numbers into the chat thanks to an awful filtering system.

Baconhair123: i have IOO coins
Noob11xx: cool

IOO by jss-urban February 4, 2021

.9.Ieeih Malcz Ioo.9. 

.9.Ieeih Malcz Ioo.9.

.9.Ieeih Malcz Ioo.9.

.9.Ieeih Malcz Ioo.9. by .6.9.7.6.ArimorylulA.8.3.0.5. September 7, 2025

IOOS 

Short for the Infinite-On-Off-Syndrome. This annoying bug sometimes happen in Facebook where the chat system turns on and off at a rapid rate.

A: Hello
B: Sup (send as message?)
A: -offline-
A: LOL
B: WTF? (send as message?)
A: -offline-
A: I got the IOOS :P
B: =.=

IOOS by WhoAmI?IamBartMan December 18, 2010

ioop 

I'm Out Of Power

I don't feel like, ioop

ioop by Shouri June 6, 2011

IOOP 

Inconsiderate of Other People

Mother: The movie starts in half an hour. Let's go.

Father: Hang on. I have to take a shower first.

Mother: Goddammit. You're so IOOP.

IOOP by Jordan110 December 13, 2012