open-ended (adj.)

Old English ende "end, conclusion, boundary, district, species, class," from Proto-Germanic *andiaz (source also of Old Frisian enda, Old Dutch ende, Dutch einde, Old Norse endir "end;" Old High German enti "top, forehead, end," German Ende, Gothic andeis "end"), originally "the opposite side," from PIE *antjo "end, boundary," from root *ant- "front, forehead," with derivatives meaning "in front of, before."

Worldly wealth he cared not for, desiring onely to make both ends meet. [Thomas Fuller, "The History of the Worthies of England," 1662]

Original sense of "outermost part" is obsolete except in phrase ends of the earth. Sense of "destruction, death" was in Old English. Meaning "division or quarter of a town" was in Old English. The end "the last straw, the limit" (in a disparaging sense) is from 1929. The end-man in minstrel troupes was one of the two at the ends of the semicircle of performers, who told funny stories and cracked jokes with the middle-man. U.S. football end zone is from 1909 (end for "side of the field occupied by one team" is from 1851). The noun phrase end-run is attested from 1893 in U.S. football; extended to military tactics by 1940. End time in reference to the end of the world is from 1917. To end it all "commit suicide" is attested by 1911. Be-all and end-all is from Shakespeare ("Macbeth" I.vii.5).

Old English open "not closed down, raised up" (of gates, eyelids, etc.), also "exposed, evident, well-known, public," often in a bad sense, "notorious, shameless;" from Proto-Germanic *upana-, literally "put or set up" (source also of Old Norse opinn, Swedish öppen, Danish aaben, Old Saxon opan, Old Frisian epen, Old High German offan, German offen "open"), from PIE root *upo "under," also "up from under," hence also "over." Related to up, and throughout Germanic the word has the appearance of a past participle of *up (v.), but no such verb has been found. The source of words for "open" in many Indo-European languages seems to be an opposite of the word for "closed, shut" (such as Gothic uslukan).

Of physical spaces, "unobstructed, unencumbered," c. 1200; of rooms with unclosed entrances, c. 1300; of wounds, late 14c. Transferred sense of "frank, candid" is attested from early 14c. Of shops, etc., "available for business," it dates from 1824.

Open-door in reference to international trading policies is attested from 1856. Open season is recorded by 1895 of game; figuratively (of persons) by 1914. Open book in the figurative sense of "person easy to understand" is from 1853. Open house "hospitality for all visitors" is first recorded 1824. Open-and-shut "simple, straightforward" first recorded 1841 in New Orleans. Open marriage, one in which the partners sleep with whomever they please, is by 1972. Open road (1817, American English) originally meant a public one; romanticized sense of "traveling as an expression of personal freedom" first recorded 1856, in Whitman.