pH

noun

\ ˈpē-ˈāch

How to pronounce pH (audio)

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Definition of pH

(Entry 1 of 2)

: a measure of acidity and alkalinity of a solution that is a number on a scale on which a value of 7 represents neutrality and lower numbers indicate increasing acidity and higher numbers increasing alkalinity and on which each unit of change represents a tenfold change in acidity or alkalinity and that is the negative logarithm of the effective hydrogen-ion concentration or hydrogen-ion activity in gram equivalents per liter of the solution also : the condition represented by a pH number

PH

abbreviation

Definition of PH (Entry 2 of 2)

1 pinch hit

2 public health

3 Purple Heart

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Time Traveler for pH

The first known use of pH was in 1909

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More Definitions for pH

pH

noun

English Language Learners Definition of pH

technical : a number between 0 and 14 that indicates if a chemical is an acid or a base

See the full definition for pH in the English Language Learners Dictionary

pH

noun

\ ˈpē-ˈāch

\

Kids Definition of pH

: a measure of the acidity or alkalinity of a substance Lemon juice has a pH of about 2.5. Water has a pH of 7.

ph

abbreviation

Medical Definition of ph

(Entry 1 of 2)

1 pharmacopoeia

2 phosphor

3 phot

pH

noun

\ (ˈ)pē-ˈāch

\

Medical Definition of pH (Entry 2 of 2)

: a measure of acidity and alkalinity of a solution that is a number on a scale on which a value of 7 represents neutrality and lower numbers indicate increasing acidity and higher numbers increasing alkalinity and on which each unit of change represents a tenfold change in acidity or alkalinity and that is the negative logarithm of the effective hydrogen-ion concentration or hydrogen-ion activity in gram equivalents per liter of the solution instead of saying that the concentration of hydrogen ion in pure water is 1.00 x 10⁻⁷, it is customary to say that the pH of pure water is 7— Linus Pauling also : the condition represented by such a number — compare pk

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to boil down or concentrate

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