inexpert vs lame duck

inexpert

noun
  • An inept or unskilled person. 

adj
  • Inept or unskilled; not of expert ability or quality. 

lame duck

noun
  • A person or thing that is helpless, inefficient, or disabled. 

  • An elected official who has lost the recent election or is not eligible for reelection and is marking time until leaving office. 

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