decline vs trend

decline

verb
  • To bend downward; to bring down; to depress; to cause to bend, or fall. 

  • To choose not to do something; refuse, forbear, refrain. 

  • To run through from first to last; to recite in order as though declining a noun. 

  • To cause to decrease or diminish. 

  • To turn or bend aside; to deviate; to stray; to withdraw. 

  • To move downwards, to fall, to drop. 

  • To inflect for case, number, gender, and the like. 

  • To reject a penalty against the opposing team, usually because the result of accepting it would benefit the non-penalized team less than the preceding play. 

  • To become weaker or worse. 

  • To recite all the different declined forms of (a word). 

noun
  • A weakening. 

  • Downward movement, fall. 

  • A reduction or diminution of activity. 

  • The act of declining or refusing something. 

  • A sloping downward, e.g. of a hill or road. 

trend

verb
  • To cause to turn; to bend. 

  • To have a particular direction; to run; to stretch; to tend. 

  • To be the subject of a trend; to be currently popular, relevant or interesting. 

  • To cleanse or clean (something, usually wool). 

noun
  • The lower end of the shank of an anchor, being the same distance on the shank from the throat that the arm measures from the throat to the bill. 

  • A line drawn on a graph that approximates the trend of a number of disparate points. 

  • The angle made by the line of a vessel's keel and the direction of the anchor cable, when she is swinging at anchor. 

  • A tendency. 

  • An inclination in a particular direction. 

  • A fad or fashion style. 

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