erm vs tsk

erm

intj
  • Used to express embarrassment or subtle disagreement. 

  • Used in hesitant speech, or to express uncertainty; um, umm. 

tsk

intj
  • An exclamation of disapproval, disappointment or discontent. 

verb
  • To make a tsk sound of disapproval. 

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