durative vs frequentative

durative

adj
  • Of or pertaining to the aspect of a verb that expresses continuing action; continuative. Part of the imperfective aspect, as opposed to the perfective aspect, of verbs. 

  • Of or pertaining to duration. 

  • Long-lasting. 

noun
  • This aspect, or a verb in this aspect; a continuative. 

frequentative

adj
  • Serving to express repetition of an action. 

noun
  • Any of a subclass of imperfective verbs that denote a repeated action, no longer productive in English, but found in e.g. Finnish, Latin, Russian, and Turkish. 

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