| Subject | English | Thesaurus |
| abbr., commun. | C/I | carrier /interference ratio |
| abbr., telecom. | CD-I | CD-interactive |
| abbr., IT | CD-I | CD Interactive |
| abbr., media. | CD-I | Compact Disc Interactive |
| abbr., scottish | CD-I | Compact Disc - Interactive |
| abbr., scottish | CD/I | Compact Disc / Interactive |
| abbr., opt. | CD/I | compact disc/interactive |
| abbr. | CD-I | Compact Disk-Interactive |
| abbr. | CD-I | Compact Disk - Interactive (CD) |
| abbr. | CD-I | Compact Disc-Interactive |
| abbr., IT | CD-I | compact disk interactive |
| abbr., snd.rec. | CD-I | compact disc interactive system |
| abbr., med. | Co I | coenzyme I |
| NASA | CO-I | Co Investigator |
| abbr., commer. | 7-Eleven is part of an international chain of convenience stores, operating under Seven-Eleven Japan Co. Ltd, which in turn is owned by Seven & I Holdings Co. of Japan.2 | 7-eleven (Pavel) |
| abbr., el. | FMV CD-I | full-motion video compact disc-interactive (system) |
| railw., abbr. | G W I Switching Services L. P. | GWSW |
| AMEX., abbr. | Glacier Water Services, Inc. Trust I | HOO PA |
| NYSE., abbr. | Hartford Financial Services Group, Inc. Capital Trust I | HIG PQ |
| AMEX., abbr. | Healthcare Integrated Services I | HII |
| energ.ind. | I&C Shop | thermal instrumentation and control shop (Kastorka) |
| abbr., avia. | I&CO | installation and checkout |
| abbr., qual.cont. | I&CO | installation and check-out |
| abbr. | I & CO | installation and checkout |
| abbr., med.appl. | I.C.R.P. | International Commission on Radiological Protection |
| abbr., telecom. | i.f. | IF |
| abbr., microel. | I²L | integrated injection logic |
| abbr., telecom. | I/O | Input (voltage earth), Output |
| abbr., avia. | I&SE | installation and service engineering |
| NYSE., abbr. | I T T Educational Services, Inc. | ESI |
| abbr., mil., commer. | Joint C4I Command, Control, Communications, Computers and Intelligence Program Assessment Tool | JCPAT (Obsolete, см. KM/DS (Knowledge Management/Decision Support Tool)) |
| NYSE., abbr. | Occidental Petroleum Corporation Capital Trust I | OXY PB |
| abbr., file.ext. | Program Controlled I/O | PC-I/O |
| telecom., abbr. | Program Controlled I/O | PCIO |
| abbr. | SE & I | system engineering and integration |
| abbr., scottish | SE&I | Systems Engineering & Integration |
| abbr., mil. | SE&I | Systems Engineering and Integration |
