freeboard vs mole

freeboard

noun
  • 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. 

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

mole

noun
  • A massive structure, usually of stone, used as a pier, breakwater or junction between places separated by water. 

  • Any of the burrowing rodents also called mole-rats. 

  • A moll, a bitch, a slut. 

  • A pigmented spot on the skin, a naevus, slightly raised, and sometimes hairy. 

  • A type of underground drain used in farm fields, in which a mole plow creates an unlined channel through clay subsoil. 

  • Any of several small, burrowing insectivores of the family Talpidae; also any of southern African mammals in the family Chrysochloridae (golden moles) and any of several Australian mammals in the family Notoryctidae (marsupial moles), similar to but not closely related to Talpidae moles 

  • An internal spy, a person who involves himself or herself with an enemy organisation, especially an intelligence or governmental organisation, to determine and betray its secrets from within. 

  • In the International System of Units, the base unit of amount of substance; the amount of substance of a system which contains exactly 6.02214076×10²³ elementary entities (atoms, ions, molecules, etc.). Symbol: mol. The number of atoms is known as Avogadro’s number. 

  • A kind of self-propelled excavator used to form underground drains, or to clear underground pipelines 

  • A hemorrhagic mass of tissue in the uterus caused by a dead ovum. 

  • A haven or harbour, protected with such a breakwater. 

  • An Ancient Roman mausoleum. 

  • One of several spicy sauces typical of the cuisine of Mexico and neighboring Central America, especially a sauce which contains chocolate and which is used in cooking main dishes, not desserts. 

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