inkling vs mental grasp

inkling

noun
  • Usually preceded by forms of to give: a slight hint, implication, or suggestion given. 

  • Often preceded by forms of to get or to have: an imprecise idea or slight knowledge of something; a suspicion. 

  • A desire, an inclination. 

mental grasp

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