Nautical, in or into a direction at right angles to the keel of a ship; directly opposite the middle part of a ship's side, and in line with its main-beam: as, we had the wind abeam.
the GNU version of the Collaborative International Dictionary of English
adverb.
On the beam, that is, on a line which forms a right angle with the ship's keel; opposite to the center of the ship's side.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
adverb.
at right angles to the length of a ship or airplane
Word Usage
"Sailboats move fastest with the wind coming from "abeam" or the side."