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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Merriam-Webster unabridged
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Time Traveler for pH
The first known use of pH was in 1909
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