aback vs discourteously

aback

adv
  • By surprise; startled; dumbfounded. (see usage) 

  • Backward against the mast; said of the sails when pressed by the wind from the "wrong" (forward) side, or of a ship when its sails are set that way. 

discourteously

adv
  • In a discourteous manner. 

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