envelop vs swallow up

envelop

verb
  • To surround or enclose. 

swallow up

verb
  • To completely enclose or envelop. 

  • To voraciously consume resources, such as money; to devour. 

  • To take over or absorb something (especially an organisation) so it no longer has a separate identity; to assimilate. 

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