doubtfully vs lastly

doubtfully

adv
  • In a doubtful manner, in context of doubt or ambiguity, questionably. 

lastly

adv
  • Used to signal that the speaker is about to yield control of the conversation. 

  • Used to mark the beginning of the last in a list of items or propositions. 

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