acidity

plural acidities

1. countableuncountableThe quality or state of being acid.
2. countableuncountableSourness; tartness; sharpness to the taste.

   the acidity of lemon juice

   1 more example

   Empty stomachs lead to acidity and leave a sour taste in the mouth.

3. countableuncountablemedicineExcessive acid quality, as in gastric secretions.
4. countablefigurativelyuncountableA caustic, sour, biting, or bitter quality.

   It was a brave, good speech, a speech from that staunch and strong spirit which lay behind all the acidities and angularities of the old zoologist.

   1913, Arthur Conan Doyle, “The Time of Death”, in The Poison Belt […], London; New York, N.Y.: Hodder and Stoughton, →OCLC, page 60

   1 more example

   "What shall we call it?" he asked. "Why should you not take the chance of perpetuating your own name?" said Summerlee, with his usual touch of acidity.

   1912, Arthur Conan Doyle, The Lost World […], London; New York, N.Y.: Hodder and Stoughton, →OCLC