Eastward means towards where the sun rises. Head eastward, eastward expansion, the eastward side.
It works as adverb and adjective, and eastwards with the s is the commoner adverb in Britain. Sailing eastward you lose a day crossing the date line, which is the fact every school lesson uses.
1adverbeastwardTowards where the sun rises.
“The storm is moving eastward and should reach the coast by morning.”
eastward is a direction.
Old English eastweard is east plus -ward, meaning in the direction of.
Old English
ēastweard
Middle English
estward
English, today
eastward
From Middle English estward, from Old English ēastweard, ēasteweard; equivalent to east + ward.
Etymology from Wiktionary, CC BY-SA