pH

\ 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

abbreviation

Definition of PH (Entry 2 of 2)

1 pinch hit

2 public health

3 Purple Heart

Examples of pH in a Sentence

Recent Examples on the Web: Noun Maidenhair ferns from other climates may like a more neutral pH, so adding a bit of lime to the soil would be to their liking. — oregonlive, "Need help hiding new neighbor’s big concrete wall? Ask an expert," 27 Dec. 2020 The fragrance-free, vitamin B3-rich formula has a 5.36 pH (similar to skin’s natural baseline) and can double as an eye cream, too. — Kari Molvar, WSJ, "We Tested 50 Face Moisturizers to Find the Best," 16 Dec. 2020 The club tests for four main parameters — phosphorus, nitrates, ammonia and chlorides — and takes the temperature and pH of the water. — Suzanne Baker, chicagotribune.com, "Banning some types of fertilizers and sealants will improve Naperville-area rivers, streams: Sierra Club," 24 Dec. 2020 If your soil has too high a pH, then nutrients become chemically locked up and unavailable. — Jeff Lowenfels, Anchorage Daily News, "How to choose poinsettias and Christmas trees," 3 Dec. 2020 Rinse the rock-wool starter cubes [D], then soak them in water with a pH of 5.5 for about an hour. — Daniel Kluko, Popular Mechanics, "Keep Growing All Winter With This DIY Hydroponic System," 7 Nov. 2020 Murdock’s pH balanced, sulfate-free beard shampoo is available in the U.S. and gets high marks for a thorough clean that removes daily grit without stripping hair follicles or skin. — Sean Piccoli, NBC News, "Best men's beard and grooming products, according to experts," 2 Nov. 2020 Research has shown that age can affect the pH of skin. — Danusia Wnek, Good Housekeeping, "Understanding Your Skin's Acid Mantle and Why It's So Important," 15 Oct. 2020 Our winter rainfall pattern tends to lower soil pH over time. — oregonlive, "Wildfire ash and smoke leave Oregon gardeners with questions: Ask an expert," 19 Sep. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'pH.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.