ahead vs rearward

ahead

adv
  • At or towards the front; in the direction one is facing or moving. 

  • To a later time. 

  • At an earlier time; beforehand; in advance. 

  • To an earlier time. 

  • In or for the future. 

  • So as to be further advanced, either spatially or in an abstract sense. 

rearward

adv
  • Toward the back or rear of something. 

adj
  • Toward the back or rear of something. 

noun
  • The last troop; the rear of an army; a rear guard. 

  • The part that comes last or is situated in the rear; conclusion, wind-up. 

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