pulley block vs sandbox

pulley block

noun
  • A shell containing one or more sheaves, the whole forming a pulley. 

sandbox

noun
  • A box filled with sand that is shaped to form a mould for metal casting. 

  • An animal's litter box. 

  • A container for sand or pounce, used historically before blotting paper. 

  • The Middle East. 

  • A children's play area consisting of a box filled with sand. 

  • A page on a wiki where users are free to experiment without destroying or damaging any legitimate content. 

  • A box carried on locomotives, from which sand runs onto the rails in front of the driving wheels, to prevent slipping. 

  • An isolated area where a program can be executed with a restricted portion of the resources available. 

verb
  • To restrict (a program, etc.) by placing it in a sandbox. 

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