Old English stan, used of common rocks, precious gems, concretions in the body, memorial stones, from Proto-Germanic *stainaz (source also of Old Norse steinn, Danish steen, Old Saxon sten, Old Frisian sten, Dutch steen, Old High German stein, German Stein, Gothic stains), from PIE *stoi-no-, suffixed form of root *stai- "stone," also "to thicken, stiffen" (source also of Sanskrit styayate "curdles, becomes hard;" Avestan stay- "heap;" Greek stear "fat, tallow," stia, stion "pebble;" Old Church Slavonic stena, Russian stiena "wall").
Sense of "testicle" is from late Old English. The British measure of weight (usually equal to 14 pounds) is from late 14c., originally a specific stone. Stone-fruit, one with a pit, is from 1520s. Stone's throw for "a short distance" is attested from 1580s. Stone Age is from 1864. To kill two birds with one stone is first attested 1650s. To leave no stone unturned is from 1540s.
"made of stone," Old English (which also had stænan "stonen"); see stone (n.). As an intensifying adjective recorded from 1935, first recorded in African-American vernacular, probably from earlier use in phrases like stone blind (late 14c., literally "blind as a stone"), stone deaf, stone-cold (1590s), etc. Stone cold sober dates from 1937.
Old English pytt (Kentish *pet), "natural or man-made depression in the ground, water hole, well; grave," from Proto-Germanic *putt- "pool, puddle" (source also of Old Frisian pet, Old Saxon putti, Old Norse pyttr, Middle Dutch putte, Dutch put, Old High German pfuzza, German Pfütze "pool, puddle"), an early borrowing from Latin puteus "well, pit, shaft."
The Latin word is perhaps from PIE root *pau- (2) "to cut, strike, stamp," but there are phonetic and sense objections.
Short u makes it impossible to directly derive puteus from paviō 'to strike'. It might be related to putāre 'to prune', but this is semantically less attractive, and the suffix -eus can then hardly be interpreted as indicating a material. Therefore, puteus may well be a loanword. [de Vaan]
Meaning "abode of evil spirits, hell" is attested from late 12c. Meaning "very small depression or dent in the surface of an object" is from early 15c. The anatomical sense of "natural depression or hollow in some part of the body" is by late 13c,; the pit of the stomach (1650s) is so called from the slight depression there between the ribs; earlier words for it were breast-pit (late 14c.), heart-pit (c. 1300).
The meaning "part of a theater on the floor of the house, lower than the stage," is from 1640s; the sense of "that part of the floor of an exchange where business is carried on" is by 1903, American English. The pit dug under a large engine or other piece of machinery to allow workers to examine or repair it is attested by 1839; this later was extended in auto racing to "area at the side of a track where cars are serviced and repaired" (by 1912).
"hard seed," 1841, from Dutch pit "kernel, seed, marrow," from Middle Dutch pitte, ultimately from Proto-Germanic *pithan-, source of pith (q.v.).
mid-15c., "to put or set in or into a pit," from pit (n.1); especially for purposes of fighting (of cocks, dogs, pugilists) from 18c. Hence the figurative sense of "to set in rivalry, match as opponents" (1754). Compare pit-bull as a dog breed, attested from 1922, short for pit-bull terrier (by 1912). The meaning "make pits in, form a little pit or hollow in" is from late 15c. Related: Pitted; pitting.
discovered 1798 at Rosetta, Egypt; now in British Museum. Dating to 2c. B.C.E., its trilingual inscription helped Jean-François Champollion decipher Egyptian demotic and hieroglyphics in 1822, which opened the way to the study of all early Egyptian records. Hence, figurative use of the term to mean "something which provides the key to previously unattainable understanding" (1902). The place name is a Europeanization of Rashid, a name given because it was founded c.800 C.E. by Caliph Harun ar-Rashid.
"edifice or project requiring constant outlay of cash with little to show for it," 1986 (year of a movie of the same name); see money (n.) + pit (n.). Before that (1930s), it was used for the shaft on Oak Island, Nova Scotia, that supposedly leads to treasure buried by Capt. Kidd or some other pirate. "Whether that name refers to the treasure or the several million dollars spent trying to get the treasure out is unclear." [Popular Mechanics, Sept. 1976]