late 14c., "front;" variant of further (adj.). From 1510s as "additional;" 1560s as "more remote."
15c. alteration of Middle English ferther (c. 1300), a variant of further (adv.). There is no historical basis for the notion that farther is of physical distance and further of degree or quality.
1640s, "on the other side of," from Latin ulterior "more distant, more remote, farther, on the farther side," comparative of *ulter "beyond" (from suffixed form of PIE root *al- "beyond"). The sense "not at present in view or consideration" (as in ulterior motives) is attested from 1735.
"unable to go any farther," 1885, past-participle adjective from stick (v.). Colloquial stuck-up "offensively conceited, assuming an unjustified air of superiority" is recorded from 1829.
Old English fyrðran, fyrðrian "to impel, urge on; advance, promote, benefit;" see further (adv.). Compare Middle Low German vorderen, Old High German furdiran, German fördern, probably from their respective adjectives via the notion in phrases such as Old English don furðor "to promote." Related: Furthered; furthering. After the further/farther split, this sense also continued in a shadow verb farther (v.), attested from 16c. but apparently dying out 19c.
Middle English fer, from Old English feor "to a great distance, long ago," from Proto-Germanic *ferro (source also of Old Saxon fer, Old Frisian fir, Old Norse fiarre, Old High German fer, Gothic fairra), from PIE root *per- (1), base of words for "through, forward," with extended senses such as "across, beyond" (source also of Sanskrit parah "farther, remote, ulterior," Hittite para "outside of," Greek pera "across, beyond," Latin per "through," Old Irish ire "farther"). For vowel change, see dark (adj.). Paired with wide to mean "everywhere" since 9c.
Old English furðor, forðor "to a more advanced position, forward, onward, beyond, more distant; farther away; later, afterward; to a greater degree or extent, in addition; moreover," etymologically representing either "forth-er" or "fore-ther." The former would be from furðum (see forth) + comparative suffix *-eron-, *-uron- (compare inner, outer).
Alternative etymology (Watkins) traces it to Proto-Germanic *furthera-, from PIE *pr-tero- (source also of Greek proteros "former"), representing the root *per- (1) "forward" + comparative suffix also found in after, other. Senses of "in addition, to a greater extent" are later metaphoric developments.
It replaced or absorbed farrer, ferrer as comparative of far (itself a comparative but no longer felt as one). Farrer itself displaced Old English fierr in this job; farrer survived until 17c., then was reduced to dialect by rival farther. "The primary sense of further, farther is 'more forward, more onward'; but this sense is practically coincident with that of the comparative degree of far, where the latter word refers to real or attributed motion in some particular direction." [OED]
Old English begeondan "on the other side of, from the farther side," from be- "by," here probably indicating position, + geond "yonder" (prep.); see yond. A compound not found elsewhere in Germanic. From late 14c. as "further on than," 1530s as "out of reach of." To be beyond (someone) "to pass (someone's) comprehension" is by 1812.
also Indochina, "Farther India, the region between India and China," 1815, from Indo- "India" + China. The name was said to have been proposed by Scottish poet and orientalist John Leyden, who lived and worked in India from 1803 till his death at 35 in 1811. French Indo-Chine is attested from 1813, but the source credits it to Leyden. The inappropriateness of the name was noticed from the start. Related: Indo-Chinese (1814).
1590s, from Greek, "daughters of the Hesperus," name given to the nymphs (variously numbered but originally three) who tended the garden with the golden apples. Their name has been mistakenly transferred to the garden itself.
The Gardens of the Hesperides with the golden apples were believed to exist in some island in the ocean, or, as it was sometimes thought, in the islands on the north or west coast of Africa. They were far-famed in antiquity; for it was there that springs of nectar flowed by the couch of Zeus, and there that the earth displayed the rarest blessings of the gods; it was another Eden. As knowledge increased with regard to western lands, it became necessary to move this paradise farther and farther out into the Western Ocean. [Alexander Murray, "Manual of Mythology," 1888]
Related: Hesperidean; Hesperidian.