SINCE 1828
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
PH
abbreviationDefinition of PH (Entry 2 of 2)
1
pinch hit
2
public health
3
Purple Heart
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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
abbreviationMedical 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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