Middle English fer, from Old English feorr "far, remote, distant," from Proto-Germanic *ferera- (cognates: Old Saxon fer, Old Frisian fer, Old Norse fjarre, Dutch ver, Old High German ferro, German fern), probably a development in western Proto-Germanic from the adverb (see far (adv.)). Far East "China, Japan, and surrounding regions" is from 1838.
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Definitions of farthest
to the greatest distance in space or time (`farthest' is used more often than `furthest' in this physical sense);