late 14c., rounden, "to make round, give roundness to," from round (adj.). Sense of "make a circuit round" is from 1590s. Sense of "bring to completeness" is from c. 1600; meaning "to approximate (a number)" is from 1934; with up or down, "to increase (or decrease) a number by adding to its last digit," by 1956. Meaning "turn round and face, turn on and assault" is from 1882. Related: Rounded; rounding.
Sense of "go past or get round" is by 1743. To round out "fill up" is by 1856. To round off is from 1680s as "make round, finish with a curved or rounded form;" by 1748 as "finish appropriately and neatly." Also compare roundup.
c. 1300 (early 13c. as a surname), "spherical in shape; circular in outline," of persons or animals, "well-fed;" from Anglo-French rounde, Old French roont (12c., Modern French rond), probably originally *redond, from Vulgar Latin *retundus (source also of Provençal redon, Spanish redondo, Old Italian ritondo), from Latin rotundus "like a wheel, circular, round," related to rota "wheel" (see rotary). The French word is the source of Middle Dutch ront (Dutch rond), Middle High German runt (German rund) and similar words in the Germanic languages.
As an adverb from c. 1300. As a preposition from c. 1600, "so as to make a complete circuit" (as in round the world); 1715 as "throughout, all through" (as in round the clock); by 1743 as "so as to make a turn or partial circuit about" (as in round the corner). In many cases it is a shortened form of around (adv.).
Of numbers from mid-14c., "entire, full, complete, brought to completion," with the notion of symmetry extended to that of completeness. Round number for one only approximately correct, usually expressed in 10s, 100s, etc., is by 1640s. Compare round (v.). Round trip "an outward and return journey" is by 1844, originally of railways. A round-dance (1520s) is one in which the dancers move in a circle or ring. Round heels attested from 1926, in reference to incompetent boxers, 1927 in reference to loose women, implying in either case a tendency to end up flat on one's back.
early 14c., "a spherical body; that which has roundness," from round (adj.) and Anglo-French rount and Old French reont, roond. Compare Dutch rond, Danish and Swedish rund, German runde, all nouns from adjectives.
The sense of "dance in which performers move in a circle or ring" is by 1510s. The meaning "large round piece of beef" is recorded from 1650s. The sense of "circuit performed by a sentinel" is from 1590s; hence to go or make one's rounds "pay regular visits" (1680s). The meaning "recurring course of time" is from 1710. Meaning "song sung by two or more, beginning at different times" is from 1520s. Golfing sense attested from 1775; card-playing sense by 1735. Of applause from 1794.
Meaning "quantity of liquor served to a company at one time" is from 1630s; that of "single bout in a fight or boxing match" is from 1812; "single discharge of a firearm" is from 1725. Sense of "recurring session of meetings or negotiations" is from 1964. Theatrical sense (in phrase in the round) in reference to a stage surrounded by the audience is recorded from 1944. To make the rounds "be passed along by a whole set of persons" is by 1967; the earlier form was go the round (1660s).
also roundtable, 1826 in reference to a gathering of persons in which all are accorded equal status (there being no head of a round table.) King Arthur's Round Table is attested from c. 1300, translating Old French table ronde (1155, in Wace's Roman de Brut).
"petition or complaint signed in a circle to disguise the order in which names were affixed and prevent ringleaders from being identified," 1730, originally in reference to sailors and frequently identified as a nautical term. As a kind of tournament in which each player plays the others, it is recorded from 1895.