freeboard vs shield

freeboard

noun
  • A type of skateboard which simulates the movement of a snowboard when used on a downhill coarse, allowing snowboarding techniques, which has an addition of two centerline casters that extend below the traditional skateboard wheels and bogies. 

  • The distance between a water level and the top of something that contains or restrains it (such as a dam). 

  • The distance between the top of sea ice and the water level. 

  • The vertical distance between the waterline and the uppermost watertight deck of a vessel. 

shield

noun
  • A framework used to protect workmen in making an adit under ground, and capable of being pushed along as excavation progresses. 

  • A large expanse of exposed stable Precambrian rock. 

  • A wide and relatively low-profiled volcano, usually composed entirely of lava flows. 

  • Parts at the front and back of a vehicle which are meant to absorb the impact of a collision 

  • A broad piece of defensive armor, held in hand, formerly in general use in war, for the protection of the body. 

  • One who protects or defends. 

  • A spot resembling, or having the form of a shield. 

  • A sign or symbol, usually containing numbers and sometimes letters, identifying a highway route. 

  • The escutcheon or field on which are placed the bearings in coats of arms. 

  • A field of energy that protects or defends. 

  • In lichens, a hardened cup or disk surrounded by a rim and containing the fructification, or asci. 

  • A police badge. 

verb
  • To protect, to defend. 

  • to protect from the influence of 

  • To shelter; to protect oneself. 

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