Phi (disambiguation)
- 6-phospho-3-hexuloisomerase
- Cyclotomic polynomial
- Euler's totient function
- Giulio Tononi
- Golden ratio
- Integrated information theory
- Isoelectric point
- Kamen Rider 555
- Krumbein phi scale
- Magnetic flux
- Nokia Lumia 920
- Normal distribution
- PHI-base
- Packard Humanities Institute
- Paraprofessional Healthcare Institute
- Pepco Holdings Inc.
- Peptide PHI
- Permanent health insurance
- Petroleum Helicopters International
- Phenyl group
- Phi
- Phi (KinKi Kids album)
- Phi (Truckfighters album)
- Phi coefficient
- Phi meson
- Phi phenomenon
- Philadelphia
- Philadelphia 76ers
- Philadelphia Eagles
- Philadelphia Flyers
- Philadelphia Phillies
- Philippines
- Post-Polio Health International
- Protected health information
- Sailor Phi
- Sesant
- Voiceless bilabial fricative
- Xeon Phi
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