inarticulate vs incoherent

inarticulate

adj
  • not articulated in normal words. 

  • unable to speak with any clarity 

  • speechless 

  • not having joints or other articulations 

noun
  • An animal belonging to the subphylum Inarticulata. 

incoherent

adj
  • Not cohering socially, not united. 

  • Not making logical sense; not logically connected or consistent. 

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