| Subject | English | Thesaurus |
| avia., Canada | abbreviated precision approach path indicator | A visual glide slope indicator (VGSI) consisting of only two light units normally situated on the left side of the runway in the form of a wing bar and indicating that the aircraft is on slope if the unit nearest the runway shows red and the unit furthest from the runway shows white, too high if both units show white, and too low if both units show red |
| aeron., abbr. | Air Speed Indicator Reading | ASIR |
| IT, abbr. | Common Part Indicator | CPI (ATM) |
| mil., abbr. | Common Part Indicator | CPI |
| abbr., avia. | Follow the ILS flight path indicators | fly the needles |
| abbr., scottish | Fuel Indicator Reading | FIR |
| abbr., scottish | Glide Path Indicator | GPI |
| abbr., scottish | Helicopter Approach Path Indicator | HAPI |
| avia. | landing direction indicator | A device to indicate visually the direction currently designated for landing and for take-off. |
| avia. | location indicator | A four-letter code group formulated in accordance with rules prescribed by ICAO and assigned to the location of an aeronautical fixed station. |
| mil., abbr. | Message Indicator | MI |
| abbr., tel. | Message Waiting Indicator | MWI (Yakov) |
| IT, abbr. | Path Overhead Indicator | POI (SONET) |
| comp., net., abbr. | Path Overhead Indicator | POI |
| telecom., abbr. | Payload Defect Indicator - Path | PDI-P |
| abbr., scottish | Precision Approach Path Indicator | PAPI |
| avia., Canada | precision approach path indicator | A visual glide slope indicator (VGSI) consisting of four light units normally situated on the left side of the runway (on both sides of the runway, in the case of the military) in the form of a wing bar and indicating that the aircraft is on slope if the two units nearest the runway show red and the two units furthest from the runway show white, too high if all units show white, and too low if all units show red. (VGSI) |
| telecom., abbr. | Remote Defect Indicator - Path | RDI-P |
| telecom., abbr. | Remote Defect Indicator - Path Level | RDI-P (SONET) |
| telecom., abbr. | Remote Error Indicator - Path Level | REI-P (SONET) |
| aeron., abbr. | Symbolic Pictorial Indicator | SPI |
| progr., abbr. | Unprocessed Message Waiting Indicator | UMWI |
| abbr., scottish | Visual Approach Path Indicator | VAPI |
| abbr., scottish | Visual Glide Path Indicator | VGPI |