Jump to:

• ph
  ph

  phot; phots.
• pH
  pH

  the symbol for the logarithm of the reciprocal of hydrogen ion concentration in gram atoms per liter, used to express the acidity or alkalinity of a solution on a scale of 0 to 14, where less than 7 represents acidity, 7 neutrality, and more than 7 alkalinity.
• Ph
  Ph

  abbreviation

  phenyl.
• ph.
  ph.

  abbreviation

  phase.
• P.H.
  P.H.

  abbreviation

  Public Health.

ph

¹ American  

Optics.

1. phot; phots.

---

pH ² American  

Chemistry.

1. the symbol for the logarithm of the reciprocal of hydrogen ion concentration in gram atoms per liter, used to express the acidity or alkalinity of a solution on a scale of 0 to 14, where less than 7 represents acidity, 7 neutrality, and more than 7 alkalinity.

---

Ph ³ American  

abbreviation

Chemistry.

1. phenyl.

---

ph. ⁴ American  

abbreviation

1. phase.

2. phone.

---

P.H. ⁵ American  

abbreviation

1. Public Health.

---

ph ¹ British  

abbreviation

1. Philippines

---

pH ² British  

noun

1. potential of hydrogen; a measure of the acidity or alkalinity of a solution equal to the common logarithm of the reciprocal of the concentration of hydrogen ions in moles per cubic decimetre of solution. Pure water has a pH of 7, acid solutions have a pH less than 7, and alkaline solutions a pH greater than 7

---

ph. ³ British  

abbreviation

1. phase

---

Ph ⁴ British  

symbol

1. phenyl group or radical

---

pH Scientific  

/ pē′āch′ /

1. A numerical measure of the acidity or alkalinity of a solution, usually measured on a scale of 0 to 14. Neutral solutions (such as pure water) have a pH of 7, acidic solutions have a pH lower than 7, and alkaline solutions have a pH higher than 7. The pH of lemon juice is 2.4; that of household ammonia is 11.5. The normal pH for human blood is 7.4.

2. ◆ The letters pH stand for potential of hydrogen, since pH is effectively a measure of the concentration of hydrogen ions (that is, protons) in a substance. The pH scale was devised in 1923 by Danish biochemist Søren Peter Lauritz Sørensen (1868–1969).

---

pH Cultural  

1. In chemistry, a measure of the strength of an acid or a base. A neutral solution has a pH of 7; acids a pH between 0 and 7; bases a pH from 7 to 14. Specially treated strips of paper (see litmus), or more precise instruments, may be used to measure pH.

---

Example Sentences

Factors such as sugar availability, pH levels, and surface chemistry could play a major role in limiting bacterial movement.

From Science Daily • Mar. 13, 2026

By adjusting the chemical composition and pH of the reactant solutions, they altered both the size and properties of the ultrasmall openings.

From Science Daily • Feb. 19, 2026

Martynas Zemavicius, a former sommelier in London restaurants, founded his company Acala in Lithuania to produce tea-based drinks that mimic the minerality, pH level and sugar content of wine.

From Barron's • Feb. 12, 2026

"Through this microcomputer and the programme I developed, and a mobile app, I can monitor various data points from the farm, such as temperature, humidity, nutrient solution concentration, and pH levels," Li told AFP.

From Barron's • Jan. 29, 2026

At dinner I share the good news: "I tested the soil. And it is neutral. The pH is a perfect 7."

From "Counting by 7s" by Holly Goldberg Sloan