mild vs sour

mild

adj
  • Not sharp or bitter; not strong in flavor. 

  • Of only moderate severity; not strict. 

  • Not serious or dangerous. 

  • Moderately warm, especially less cold than expected. 

  • Gentle and not easily angered. 

  • Not overly felt or seriously intended. 

  • Acting gently and without causing harm. 

noun
  • A relatively low-gravity beer, often with a dark colour; mild ale 

sour

adj
  • Having an acidic, sharp or tangy taste. 

  • Unfortunate or unfavorable. 

  • Peevish or bad-tempered. 

  • Off-pitch, out of tune. 

  • Made rancid by fermentation, etc. 

  • Excessively acidic and thus infertile. 

  • Tasting or smelling rancid. 

  • Containing excess sulfur. 

verb
  • To make sour. 

  • To become sour. 

  • To spoil or mar; to make disenchanted. 

  • To become disenchanted. 

  • To make (soil) cold and unproductive. 

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

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

noun
  • A drink made with whiskey, lemon or lime juice and sugar. 

  • The acidic solution used in souring fabric. 

  • Any cocktail containing lemon or lime juice. 

  • A sour or acid substance; whatever produces a painful effect. 

  • The sensation of a sour taste. 

How often have the words mild and sour occurred in a corpus of books? (source: Google Ngram Viewer )