From side to side, often in an oblique manner; across or over. / Across the path of something, so as to impede progress.

From one side to the other side of; across. / Across the course or path of, so as to meet; hence (figuratively), to the attention of. / Across the course or path of, so as to oppose. / Across; through.

(nautical) Across the vessel sideways, i.e. in a direction at right angles to the fore-and-aft line of the vessel.

(nautical) Oriented across the vessel sideways, i.e. in a direction at right angles to the fore-and-aft line of the vessel.

Alternative form of athwartships

athwart; in a side-to-side orientation