PH most commonly refers to:
- pH, a measure of acidity or alkalinity.
- Philippines (ISO country code PH), a country located in Southeast Asia
PH, ph, pH, and Ph may also refer to:
Arts and media
- PistonHeads, a motoring website and forum
- PH (band), formerly known as Mr. Peter Hayden, a Finnish band
- Pornhub, a pornographic video sharing website
Aviation
- PH, Aircraft registration prefix for the Netherlands
- Polynesian Airlines (IATA airline designator)
- Transavia.com Denmark (IATA airline designator)
Companies and organizations
- Parker-Hannifin Corporation (stock ticker PH)
- Pakatan Harapan (also known as "Alliance of Hope"), a political coalition in Malaysia
Places
- Port Harcourt, (alternative name of the city)
- Preston Hollow, Dallas, a neighborhood
Science and technology
Chemistry
- Phenyl group, either -Ph or Φ, highly-stable and aromatic hydrocarbon unit found in many organic compounds
- Pleckstrin homology domain, a part of many proteins which bind phosphoinositides with high affinity
Computing
- .ph, the Philippines' Internet country code top-level domain
- Ph protocol, an early web database search for CCSO Nameserver described by RFC 2378
- PH (complexity), the union of all complexity classes in the polynomial hierarchy in computational complexity theory
Physics
- Phot, or ph, a measurement of illuminance, in photometry
- Picohenry, an SI Unit of electrical inductance
Other sciences
- Planet Hunters, a group that hunts for exoplanets
- Precipitation hardening, a heat treatment technique used to increase the yield strength of malleable materials
- Pulmonary hypertension, a medical condition
Other uses
- pʰ, a phoneme
- Ph (digraph), a common digraph that represents the phoneme /f/ (voiceless labiodental fricative) in phonetics
- PH, abbreviation for professional hunter used in East and Southern Africa
- (ph), a notation used in transcripts to indicate that the transcriber does not know the spelling, usually of a name, and has spelled it as it was pronounced (phonetically)
- Poul Henningsen (1894–1967), a Danish writer and designer referred to as PH in Denmark
- Public house, most commonly referred to as pub, an establishment licensed to serve alcoholic drinks
- Purple Heart, a US military award, in post-nominal designation
- Pinch hitter, in baseball
- abbreviation used to denote the English regnal years of Philip II of Spain
- Pḥ, abbreviation (e.g. on maps) for parish, also in the meaning of civil parish
- Phillips type of cross-head screw drive bits
See also
- Phi (φ), a letter of the Greek alphabet