Athwart means across from side to side. Lie athwart the deck, athwart the current, moored athwart.
It is chiefly a sailor's word and it survives mainly at sea, where athwartships means across the vessel rather than fore and aft. Figuratively, to run athwart something is to go against it. The thwart in it is the old word for crosswise, and a thwart is also a rower's bench.
1prepositionathwartAcross from side to side.
“A fallen tree lay athwart the path, blocking our way.”
athwart is a position.
From a- plus thwart, crosswise, from Old Norse thvert, across. A thwart in a boat is a crosswise bench.
Proto-Indo-European
*terkʷ-
Proto-Germanic
*þwerhaz — cross; adverse
Old Norse
þvert — across, athwart
Middle English
athwert
English, today
athwart
Built from
From Late Middle English athwert, athirt, from a- + thwert (“crosswise; (cooking) across the grain”). Thwert is derived from thwert (“crosswise, transverse; counter, opposing; contrary, obstinate, stubborn”), borrowed from Old Norse þvert (“across, athwart”), originally the neuter form of þverr (“across, transverse”), from Proto-Germanic þwerhaz (“cross; adverse”) (altered or influenced by Proto-Germanic þweraną (“to stir; to swirl; to turn”)), from Proto-Germanic þerh-, probably from Proto-Indo-European terkʷ- (“to spin; to turn”). The English word is analysable as a + thwart. 2
Etymology from Wiktionary, CC BY-SA