| Abbreviation | Definition |
|---|---|
| ISS | Instant Space Station |
| ISS | Institute Of Silly Strings |
| ISTP | I Summon The Power |
| ISTP | International Slave Trading Program |
| ISU | I Screwed Up |
| ISU | I Support Usagi |
| ISU | Ill-and-noisey Soviet University |
| ISU | Ill-a-noise State University |
| ISU | Illinois Socialist University |
| IT | Impotent Technician |
| ITALY | I Trust And Love You |
| ITALY | I Trust And Love You or I'm Thinking About Loving You |
| ITBROOTP | In The Bathroom, Out Of Toothpaste |
| ITCIHP | Its Too Crazy In Here People |
| ITSM | I Take Some Money |
| ITT | I'm Totally Terrific |
| ITTOOTP | In The Toilet Out Of Toilet Paper |
| ITTTOI | In To The Thick Of It |
| ITTTOI | In to the thick of ot |
| ITV | Its Terry Venables |