ambulate vs trudge

ambulate

verb
  • To walk; to relocate oneself under the power of one's own legs. 

trudge

verb
  • To walk wearily with heavy, slow steps. 

  • To trudge along or over a route etc. 

noun
  • A tramp, i.e. a long and tiring walk. 

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