flotsam vs shipwreck

flotsam

noun
  • Debris floating in a river or sea, in particular fragments from a shipwreck. 

shipwreck

noun
  • A ship that has sunk or run aground so that it is no longer seaworthy. 

  • An event where a ship sinks or runs aground. 

  • destruction; ruin; irretrievable loss 

verb
  • To wreck a boat through a collision or mishap. 

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