[1] : The Collaborative International Dictionary of English v.0.48

afterwards \aft"erwards\, afterward \aft"erward\, adv. as.
   aefteweard, a., behind. see aft, and -ward suffix.
   the final s in afterwards is adverbial, orig. a genitive
   ending.
   at a later or succeeding time.
   1913 webster
see also:
aft -ward 

[2] : WordNet (r) 2.0

afterward
     adv : happening at a time subsequent to a reference time; "he
           apologized subsequently"; "he's going to the store but
           he'll be back here later"; "it didn't happen until
           afterward"; "two hours after that" syn: subsequently,
            later, afterwards, after, later on
see also:
subsequently later afterwards after later on 

Afterward >> A Words
Afterward, definition of term: Afterward
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