absurdity vs absurdum

absurdity

noun
  • That which is absurd; an absurd action; a logical contradiction. 

  • The quality of being absurd or inconsistent with obvious truth, reason, or sound judgment. 

absurdum

noun
  • An illogical conclusion or state. 

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