Athwart; being at right angles to the line of sight: as, thwartwise motion. Such motion of a star is deducible from the star' s proper motion when its parallax is known.
WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
adj. extending or lying across; in a crosswise direction; at right angles to the long axis
Word Usage
"There was a trough running thwartwise of the ship into which the water had to be lifted from the midship well."