Entries related to four-corners
"1 more than three, twice two; the number which is one more than three; a symbol representing this number;" Old English feower "four; four times," from Proto-Germanic *fedwores (source also of Old Saxon fiuwar, Old Frisian fiower, fiuwer, Frankish *fitter-, Dutch vier, Old High German fior, German vier, Old Norse fjorir, Danish fire, Swedish fyra, Gothic fidwor "four"), from PIE root *kwetwer- "four." The phonetic evolution of the Germanic forms has not been fully explained; Watkins explains the -f- as being from the following number (Modern English five).
To be on all fours is from 1719; earlier on all four (14c.). Four-letter word as a euphemism for one of the short words generally regarded as offensive or objectionable is attested from 1923; four-letter man is recorded from 1920 (apparently as a euphemism for a shit). Compare Latin homo trium litterarum, literally "three-letter man," a euphemism for fur "a thief." A four-in-hand (1793) was a carriage drawn by four horses driven by one person; in the sense of "loosely tied necktie" it is attested from 1892. To study The History of the Four Kings (1760, compare French Livres des Quatre Rois) contains an old euphemistic slang phrase for "a pack of cards," from the time when card-playing was considered a wicked pastime for students. Slang 4-1-1 "essential information" (by 1993) is from the telephone number called to get customer information. The four-color problem so called from 1879. The four-minute mile was attained 1954.
late 13c., "place where streets or walls meet;" early 14c., "intersection of any two converging lines or surfaces; an angle," from Anglo-French cornere (Old French corner, corniere), from Old French corne "horn; corner," from Vulgar Latin *corna, from Latin cornua, plural of cornu "horn, hard growth on the head of many mammals," from PIE root *ker- (1) "horn; head."
Latin cornu was used of pointed or stiff things but not of corners, for which angulus was the word. Meaning "a region or district" is from late 14c.; the four corners of the known earth is from late 14c. Sense of "either of the places where the upper and lower eyelids meet" is from late 14c. Meaning "a small, secret, or retired place" is from late 14c.
In boxing, from 1853. In soccer, short for corner-kick, by 1882. Sense of "a monopolizing of the market supply of a stock or commodity" is from 1853. As an adjective, from 1530s. Corner-shop is from late 13c.
To turn the corner "change direction," literally or figuratively, is from 1680s. To be just around the corner in the extended sense of "about to happen" is by 1905. To cut corners is by 1847 as "pass round a corner or corners as closely as possible;" figurative use, in reference to an easy or economical but risky course of action, is by 1882.