hobby horse vs soapbox

hobby horse

noun
  • A topic about which someone loves to talk at great length. 

  • A child's toy consisting of a (usually wooden or cloth) horse's head mounted on a stick. 

  • The Irish hobby, an extinct breed of horse. 

  • A puppet-like costume used in some traditional dances and festivals that gives its wearer the appearance of a man on horseback. 

  • An early bicycle with no pedals or brakes; a draisienne. 

soapbox

noun
  • A talk about one's pet topic (or the topic itself), especially when only tangentially relevant to an ongoing discussion. 

  • A soapbox car. 

  • A crate for packing soap. 

  • Any physical or media platform which gives prominence to the person on it and the views they espouse. 

verb
  • To give a speech from (or as if from) a soapbox. 

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