laggardly vs lethargically

laggardly

adv
  • In the manner of a laggard; sluggishly; slowly. 

adj
  • Slow in manner; taking more time than is necessary; lagging behind. 

lethargically

adv
  • In a lethargic manner, without energy, tiredly. 

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