Quantcast
Merriam-Webster Logo
  • Dictionary
  • Thesaurus
  • Scrabble
  • Spanish Central
  • Learner's Dictionary

pH

play
noun \ˈpē-ˈāch\

Simple Definition of pH

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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of pH

  1. :  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

Origin of ph

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


First Known Use: 1909


PH

abbreviation

Definition of PH

  1. 1 pinch hit

  2. 2 public health

  3. 3 Purple Heart




Medical Dictionary

ph

abbreviation

Medical Definition of ph

  1. 1pharmacopoeia

  2. 2phosphor

  3. 3phot




pH

play
noun \(ˈ)pē-ˈāch\

Medical Definition of pH

  1. :  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 7—Linus Pauling>; also :  the condition represented by such a number—compare pk




Learn More about ph


Seen and Heard

What made you want to look up pH? Please tell us where you read or heard it (including the quote, if possible).

WORD OF THE DAY

expressing little or no emotion

Get Word of the Day daily email!

WORD GAMES

Take a 3-minute break and test your skills!

Name That Thing

Test your visual vocabulary with our 10-question challenge!

TAKE THE QUIZ
SCRABBLE® Sprint

Test Your Knowledge - and learn some interesting things along the way.

TAKE THE QUIZ