front line vs van

front line

noun
  • A low level. 

  • attack, collectively the attackers or forwards. 

  • A site of a conflict, effort, or controversial matter of any kind. 

  • A front, or a boundary between opposing positions. 

  • The site of interaction with outsiders, such as customers. 

van

verb
  • To wash or cleanse, as a small portion of ore, on a shovel. 

  • To transport in a van or similar vehicle (especially of horses). 

  • Of law enforcement: to arrest (not necessarily in a van; derived from party van). 

noun
  • A large towable vehicle equipped for the repair of structures that cannot easily be moved. 

  • A shovel used in cleansing ore. 

  • A fan or other contrivance, such as a sieve, for winnowing grain. 

  • A covered motor vehicle used to carry goods or (normally less than ten) persons, usually roughly cuboid in shape, longer and higher than a car but relatively smaller than a truck/lorry or a bus. 

  • A wing with which the air is beaten. 

  • An enclosed railway vehicle for transport of goods, such as a boxcar/box van. 

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