mouth off vs rant

mouth off

verb
  • To complain or otherwise express oneself in a loud, immoderate manner. 

  • To talk impudently, especially to one's superior. 

rant

verb
  • To criticize by ranting. 

  • To speak or shout at length in uncontrollable anger. 

  • To dance rant steps. 

  • To disseminate one's own opinions in a - typically - one-sided, strong manner. 

noun
  • A wild, emotional, and sometimes incoherent articulation. 

  • A criticism done by ranting. 

  • A type of dance step usually performed in clogs, and particularly (but not exclusively) associated with the English North West Morris tradition. The rant step consists of alternately bringing one foot across and in front of the other and striking the ground, with the other foot making a little hop. 

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