A solution with a pH of 8 would be considered acidic in ethanol, but basic in water! The Theoretical Definition pH has been more accurately defined as pH = -log aH+ where aH+ is the hydrogen ion activity. In solutions that contain other ions, activity and concentration are not the same.
http://antoine.frostburg.edu/chem/senese/101/acidbase/faq/what-is-pH.shtml
Noun. 1. pH - (from potential of Hydrogen) the logarithm of the reciprocal of hydrogen-ion concentration in gram atoms per liter; provides a measure on a scale from 0 to 14 of the acidity or alkalinity of a solution (where 7 is neutral and greater than 7 is more basic and less than 7 is more acidic);
http://www.thefreedictionary.com/PH+level
The Simple Definition. pH is a logarithmic measure of hydrogen ion concentration, originally defined by Danish biochemist S ren Peter Lauritz S rensen in 1909 [ 1 ]. pH = -log[H+]. where log is a base-10 logarithm and [H+] is the concentration of hydrogen ions in moles per liter of solution. According to the Compact Oxford English Dictionary, the p stands for the German word for power, potenz, so pH is an abbreviation for power of hydrogen [ 2 ].
http://antoine.frostburg.edu/chem/senese/101/acidbase/faq/what-is-pH.shtml
pH. A scale which gives a measure of the acidity of an aqueous solution. A neutral solution has a pH of 7; an acidic solution has a lower value, and an alkaline solution a higher value.
http://www.thefreedictionary.com/PH+level
Definition. A measure of acidity or alkalinity of water soluble substances (pH stands for 'potential of Hydrogen'). A pH value is a number from 1 to 14, with 7 as the middle (neutral) point. Values below 7 indicate acidity which increases as the number decreases, 1 being the most acidic. Values above 7 indicate alkalinity which increases as the number increases, 14 being the most alkaline.
http://www.businessdictionary.com/definition/pH-scale.html
It is a logarithmic scale in which two adjacent values increase or decrease by a factor of 10. For example, a pH of 3 is ten times more acidic than a pH of 4, and 100 times more acidic than a pH of 5. Similarly, a pH of 9 is 10 times more alkaline than a pH of 8, and 100 more alkaline than a pH of 7.
http://www.businessdictionary.com/definition/pH-scale.html
A measure of the acidity or alkalinity of a solution, numerically equal to 7 for neutral solutions, increasing with increasing alkalinity and decreasing with increasing acidity. The pH scale commonly in use ranges from 0 to 14. p(otential of) h(ydrogen) .
http://www.yourdictionary.com/ph
the pH is equal to minus the log of the H+ concentration. For example is the H+ concentration is very low, lets say about 0.0000001M, then the pH is.
http://academic.brooklyn.cuny.edu/biology/bio4fv/page/ph_def.htm
pH. n. 1. (Chemistry) potential of hydrogen; a measure of the acidity or alkalinity of a solution equal to the common logarithm of the reciprocal of the concentration of hydrogen ions in moles per cubic decimetre of solution.
http://www.thefreedictionary.com/PH+level
What is pH. pH is a measure of the hydorgen ion concentration of a solution. Solutions with a high concentration of hydrogen ions have a low pH and solutions with a low concentrations of H+ ions have a high pH. This may seem like a confusion way to express these reationships, and it is, until you understand what pH stands for.
http://academic.brooklyn.cuny.edu/biology/bio4fv/page/ph_def.htm
define ph
Potential of Hydrogen is a scale which gives a measure of the acidity of an aqueous solution. pH is a scale which gives a measure of the acidity of an aqueous solution.