pH is defined as the degree of acidity or alkalinity of a solution.(abbreviation)
An example of a pH is 7 for distilled water, which mean it's neutral.
See P & H in Webster's New World College Dictionary
Origin: < Fr p(ouvoir) h(ydrogène), lit., hydrogen power
See P & H in American Heritage Dictionary 4
Origin: p(otential of) h(ydrogen).
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