Simple Definition of pH

from our Learner's Dictionary

pH

noun

ˈpiːˈeɪtʃ

technical : a number between 0 and 14 that indicates if a chemical is an acid or a base

Note: A chemical with a pH lower than 7 is an acid, and a chemical with a pH higher than 7 is a base.

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“PH.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/pH. Accessed 21 Jun. 2026.

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