Old English east, eastan (adj., adv.) "east, easterly, eastward;" easte (n.), from Proto-Germanic *aust- "east," literally "toward the sunrise" (source also of Old Frisian ast "east," aster "eastward," Dutch oost Old Saxon ost, Old High German ostan, German Ost, Old Norse austr "from the east"), from PIE root *aus- (1) "to shine," especially of the dawn. The east is the direction in which dawn breaks. For theory of shift in the geographical sense in Latin, see austral.
As one of the four cardinal points of the compass, from c. 1200. Meaning "the eastern part of the world" (from Europe) is from c. 1300. Cold War use of East for "communist states" first recorded 1951. French est, Spanish este are borrowings from Middle English, originally nautical. The east wind in Biblical Palestine was scorching and destructive (as in Ezekiel xvii.10); in New England it is bleak, wet, unhealthful. East End of London so called by 1846; East Side of Manhattan so called from 1871; East Indies (India and Southeast Asia) so called 1590s to distinguish them from the West Indies.
adverbial suffix expressing direction, Old English -weard "toward," literally "turned toward," sometimes -weardes, with genitive singular ending of neuter adjectives, from Proto-Germanic *werda- (cognates: Old Saxon, Old Frisian -ward, Old Norse -verðr), variant of PIE *werto- "to turn, wind," from root *wer- (2) "to turn, bend." The original notion is of "turned toward."