The American Heritage® Dictionary of the English Language, 4th Edition
ad. On board a ship, train, aircraft, or other passenger vehicle.
ad. At the side; alongside.
ad. In or into a group, organization, or business: brought aboard two new designers.
ad. Baseball On base.
preposition. On board of; on; in.
the GNU version of the Collaborative International Dictionary of English
ad. On board; into or within a ship or boat; hence, into or within a railway car.
ad. Alongside.
preposition. On board of.
preposition. Across; athwart.
The Century Dictionary and Cyclopedia
On the deck or in the hold of a ship or vessel; into or upon a vessel.
Alongside; by the side; on one side.
On board; into.
Upon; across; athwart.
n. Approach. Also spelled abord.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
ad. part of a group
ad. on a ship, train, plane or other vehicle
ad. on first or second or third base
ad. side by side
Word Usage
"Captain Hollinger -- for he assumed this title aboard the _Seamew_ -- looked at the two boys amusedly, then took each by an arm and propelled them toward the companionway."