From WordNet (r) 3.0 (2006) [wn]:
aboard
adv 1: on a ship, train, plane or other vehicle [syn: aboard,
on board]
2: on first or second or third base; "Their second homer with
Bob Allison aboard" [syn: aboard, on base]
3: side by side; "anchored close aboard another ship" [syn:
aboard, alongside]
4: part of a group; "Bill's been aboard for three years now"
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Aboard \A*board"\, prep.
1. On board of; as, to go aboard a ship.
[1913 Webster]
2. Across; athwart. [Obs.]
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Nor iron bands aboard
The Pontic Sea by their huge navy cast. --Spenser.
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From The Collaborative International Dictionary of English v.0.48 [gcide]:
Aboard \A*board"\, adv. [Pref. a- on, in + board.]
1. On board; into or within a ship or boat; hence, into or
within a railway car.
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2. Alongside; as, close aboard.
[1913 Webster] (Naut.):
To fall aboard of, to strike a ship's side; to fall foul
of.
To haul the tacks aboard, to set the courses.
To keep the land aboard, to hug the shore.
{To lay (a ship) aboard}, to place one's own ship close
alongside of (a ship) for fighting.
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