pH

1 of 2

noun

: 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

2 of 2

abbreviation

1
pinch hit
2
public health
3
Purple Heart

Examples of pH in a Sentence

Recent Examples on the Web
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Noun
Lower Soil pH Wood ash has a high pH, usually around 10 to 12, says Chelsea McKinley, plant health specialist at the U.S. Botanic Garden in Washington, D.C. Leanne Potts, Better Homes & Gardens, 17 Sep. 2024 This is because lower gastric pH facilitates better iron absorption. Stephen C. George, Discover Magazine, 12 Feb. 2024 Then several sample portions are measured for nutrient content, pH and organic matter. Lauren David, Washington Post, 13 Nov. 2023 Soil pH is defined as the acidity or alkalinity of the soil. Rita Perwich, San Diego Union-Tribune, 4 Nov. 2023 See all Example Sentences for pH 

Word History

Etymology

Noun

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

First Known Use

Noun

1909, in the meaning defined above

Time Traveler
The first known use of pH was in 1909

Dictionary Entries Near pH

Cite this Entry

“PH.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/pH. Accessed 26 Dec. 2024.

Kids Definition

: a number used in expressing acidity or alkalinity on a scale whose values run from 0 to 14 with 7 representing neutrality, numbers less than 7 increasing acidity, and numbers greater than 7 increasing alkalinity
also : the condition represented by such a number

Medical Definition

ph

1 of 2 abbreviation
1
pharmacopoeia
2
phosphor
3
phot

pH

2 of 2 noun
: 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 7Linus Pauling
also : the condition represented by such a number compare pk

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