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

eastbound \eastbound\ adj.
   1. moving toward the east; as, eastbound trains.

   syn: eastward.
        wordnet 1.5

   2. designated for traffic moving toward the east; -- of lanes
      in roads or railroads, or other traffic lanes; as, the
      eastbound lanes of interstate 80 are blocked by an
      overturned tractor-trailer; the train will leave on
      eastbound platform 5.
      pjc

[2] : WordNet (r) 2.0

eastbound
     adj : moving toward the east; "eastbound trains" syn: eastward
see also:
eastward 

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