souring

verb
  1. 1

    To make sour.

    โ€œToo much lemon juice will sour the recipe.โ€

  2. 2

    To become sour.

  3. 3

    To spoil or mar; to make disenchanted.

  4. 4

    To become disenchanted.

    โ€œWe broke up after our relationship soured.โ€

  5. 5

    To make (soil) cold and unproductive.

  6. 6

    To macerate (lime) and render it fit for plaster or mortar.

  7. 7

    To process (fabric) after bleaching, using hydrochloric acid or sulphuric acid to wash out the lime.

noun
  1. 1

    The process by which something is made, or becomes, sour.

  2. 2

    The process by which fabric is soured, washing out the lime by means of acid.

  3. 3

    Any sour apple.

  4. 4

    Vinegar.

Source: https://en.wiktionary.org/wiki/sour, https://en.wiktionary.org/wiki/souring