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

eastward \east"ward\, eastwards \east"wards\, adv.
   toward the east; in the direction of east from some point or
   place; as, new haven lies eastward from new york.
   1913 webster

[2] : WordNet (r) 2.0

eastward
     adj : moving toward the east; "eastbound trains" syn: eastbound
     adv : toward the east; "they migrated eastward to sweden" syn: eastwards
see also:
eastbound eastwards 

Eastward >> E Words
Eastward, definition of term: Eastward
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