bulwark vs mole

bulwark

noun
  • A breakwater. 

  • A defensive wall or rampart. 

  • A defense or safeguard. 

  • Any means of defence or security. 

  • The planking or plating along the sides of a nautical vessel above her gunwale that reduces the likelihood of seas washing over the gunwales and people being washed overboard. 

verb
  • To fortify something with a wall or rampart. 

  • To provide protection of defense for something. 

mole

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

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

  • A moll, a bitch, a slut. 

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

  • 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. 

  • 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 bulwark and mole occurred in a corpus of books? (source: Google Ngram Viewer )