endlessly in WordNet English dictionary

1. with unflagging resolve
   "dance inspires him ceaselessly to strive higher and higher toward the shining pinnacle of perfection that is the goal of every artiste"
   endlessly  ceaselessly  incessantly  unceasingly  unendingly  continuously  endlessly  ceaselessly  incessantly  unceasingly  unendingly  continuously 
   
2. continuing forever without end
   "there are infinitely many possibilities"
   infinitely  endlessly  infinitely  endlessly 
   
3. all the time; seemingly without stopping
   "a theological student with whom I argued interminably"; "her nagging went on endlessly"
   interminably  endlessly  interminably  endlessly 
   
4. (spatial sense) without bounds
   "the Nubian desert seemed to stretch out before them endlessly"
   endlessly  endlessly