dissertation vs lecture

dissertation

noun
  • A lengthy lecture on a subject; a treatise; a discourse; a sermon. 

  • A formal exposition of a subject, especially a research paper that students write in order to complete the requirements for a doctoral degree in the US and a non-doctoral degree in the UK; a thesis. 

lecture

noun
  • a class that primarily consists of a (weekly or other regularly held) lecture (as in sense 1) 

  • A berating or scolding. 

  • A spoken lesson or exposition, usually delivered to a group. 

verb
  • To preach, to berate, to scold. 

  • To teach (somebody) by giving a speech on a given topic. 

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