pH

noun
\ˈpē-ˈāch \

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

Definition of PH (Entry 2 of 2)

1 pinch hit

2 public health

3 Purple Heart

First Known Use of pH

Noun

1909, in the meaning defined above

History and Etymology for pH

Noun

German, from Potenz power + H (symbol for hydrogen)

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Dictionary Entries near pH

pgn

PGT

PH

pH

phac-

phacelia

phacella

Statistics for pH

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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

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

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.

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

More from Merriam-Webster on pH

Spanish Central: Translation of pH

Nglish: Translation of pH for Spanish Speakers

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