- apparent superluminal velocity
- apparent temperature
- apparent time
- apparent-time studies
- apparent value
- apparent velocity
- apparent vertex
- apparent viscosity
- apparent viscosity of melt
- apparent visual magnitude
- apparent volume of distribution
- apparent zenith distance
- apparition
- AP-PCR
- APP Design
- appeal to emotion
- appeal to rationality
- appeal to the higher authorities
- appearance and non-appearance
- appearance and texture representation
- appearance and thing-in-itself
- appearance height
- appearance in the day
- appearance point
- appearance potential