hurdle vs obstruction

hurdle

noun
  • An obstacle, real or perceived, physical or abstract. 

  • An artificial barrier, variously constructed, over which athletes or horses jump in a race. 

  • A movable frame of wattled twigs, osiers, or withes and stakes, or sometimes of iron, used for enclosing land, for folding sheep and cattle, for gates, etc.; also, in fortification, used as revetments, and for other purposes. 

verb
  • To compete in the track and field events of hurdles (e.g. high hurdles). 

  • To overcome an obstacle. 

  • To jump over something while running. 

  • To hedge, cover, make, or enclose with hurdles. 

obstruction

noun
  • Something which obstructs or impedes, either intentionally or unintentionally 

  • The act of obstructing, or state of being obstructed. 

  • The condition of having the natural powers obstructed in their usual course; the arrest of the vital functions; death. 

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