connoisseur vs freshman

connoisseur

noun
  • A specialist in a given field whose opinion is highly valued, especially in one of the fine arts or in matters of taste. 

freshman

noun
  • A person (of either sex) entering the first year of an institution, especially a high school (ninth grade for US and Canada, grade 7 for Philippines), a university, or legislative body. 

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