- Baseline totals — hours carried forward from a previous logbook as a single summary entry.
- Catenary — the sagging curve of a wire strung between two towers. The wire hangs well below the towers, which is why obstacle heights alone understate wire-strike risk.
- Civil twilight — the period when the sun is between the horizon and 6° below it. Civil dawn and civil dusk bound the period in which the horizon is generally visible.
- Density altitude — pressure altitude corrected for non-standard temperature; the altitude the aircraft thinks it is at for performance purposes.
- Dual given / dual received — instruction logged by the instructor / by the student for the same flight.
- MSA — minimum safe altitude; the lowest altitude providing obstacle clearance in a defined area.
- METAR / TAF — an observation of current conditions / a forecast for an airport terminal area.
- NOTAM — Notice to Air Missions: temporary changes to facilities, procedures or hazards.
- PIC — pilot in command.
- SIGMET / AIRMET — significant / airmen's meteorological information about en-route hazards.
- TFR — temporary flight restriction.
- Time in type — hours flown in a specific make and model, as opposed to total time.
- Winds and temperatures aloft — forecast wind and temperature at altitude, used for groundspeed, fuel burn and turbulence expectations.