cloverleaf vs crosswalk

cloverleaf

verb
  • To turn by following a cloverleaf, or as if by following one. 

adj
  • In the form of the leaf of a clover plant; cloverleafed. 

noun
  • (with plural cloverleafs or cloverleaves) A cloverleaf interchange. 

  • The leaf of a clover plant 

crosswalk

noun
  • A mapping between equivalent elements (fields) in different database schemas. 

  • A point designated for pedestrians to cross a street. 

verb
  • To map equivalent elements (fields) in different database schemas. 

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