the taste experience when something acidic is taken into the mouth
"The sharp acidity of the lemon immediately made her pucker her lips."
pH values below 7
"The gardener tested the soil's acidity before adding lime to ensure the pH was not too low for the tomatoes."
The quality or state of being acid.
"The acidity of the soil was too high for these delicate plants to survive."
The word acidity comes from the French acidité and the Latin aciditās, which originally meant "sourness." It is formed by combining the root for "sour" with a suffix meaning the state of being so.