burden vs flagship

burden

noun
  • The capacity of a vessel, or the weight of cargo that she will carry. 

  • A phrase or theme that recurs at the end of each verse in a folk song or ballad. 

  • The proportion of ore and flux to fuel, in the charge of a blast furnace. 

  • A responsibility, onus. 

  • The tops or heads of stream-work which lie over the stream of tin. 

  • A fixed quantity of certain commodities. 

  • Theme, core idea. 

  • The drone of a bagpipe. 

  • A cause of worry; that which is grievous, wearisome, or oppressive. 

  • The total amount of toxins, parasites, cancer cells, plaque or similar present in an organism. 

  • A heavy load. 

verb
  • To impose, as a load or burden; to lay or place as a burden (something heavy or objectionable). 

  • To encumber with a literal or figurative burden. 

flagship

noun
  • The ship regarded as most important out of a group, e.g. a nation's navy or company's fleet. 

  • The most important one out of a related group. 

  • The ship occupied by the fleet's commander (usually an admiral); it denotes this by flying his flag. 

verb
  • To act as a flagship for. 

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