| MPF | maturation promoting factor; mean power frequency |
|---|---|
| n | Greek letter nu; degrees of freedom; frequency; kinematic velocity; neutrino |
| OIF | observed intrinsic frequency; oil immersion field; Osteogenesis Imperfecta Foundation |
| PRF | partial reinforcement; patient report form; perforin; plasma recognition factor; pontine reticular f... |
| PSIL | preferred frequency speech interference level |