knotty question vs teaser

knotty question

teaser

noun
  • The stoker of a glassworks furnace. 

  • A brief portion of a television episode shown at the beginning, often before the main title sequence, meant to introduce the story and entice viewers to watch the rest of the episode. 

  • A shunt winding on field magnets for maintaining their magnetism when the main circuit is open. 

  • A short horizontal curtain used to mask the flies and frame the top of the inner stage opening, adjustable to the desired height. 

  • One who teases or pokes fun. 

  • A person or thing that teases. 

  • A kind of gull, the jaeger. 

  • A preview or part of a product released in preparation of its main advertising, typically a short film, song, or quote. 

  • An assistant who accompanies the 'Obby 'Oss in the May Day festivities of Padstow, Cornwall. 

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