rugrat (n.)youdaoicibaDictYouDict[rugrat 词源字典]
also rug-rat, "baby, child," by 1968; see rug + rat (n.).[rugrat etymology, rugrat origin, 英语词源]
ruin (n.)youdaoicibaDictYouDict
late 14c., "act of giving way and falling down," from Old French ruine "a collapse" (14c.), and directly from Latin ruina "a collapse, a rushing down, a tumbling down" (source also of Spanish ruina, Italian rovina), related to ruere "to rush, fall violently, collapse," from PIE *reue- (2) "to smash, knock down, tear out, dig up" (see rough (adj.)). Meaning "complete destruction of anything" is from 1670s. Ruins "remains of a decayed building or town" is from mid-15c.; the same sense was in the Latin plural noun.
ruin (v.)youdaoicibaDictYouDict
1580s (transitive), from ruin (n.). Intransitive sense "fall into ruin" is from c. 1600. Financial sense is attested from 1660. Related: Ruined; ruining.
ruination (n.)youdaoicibaDictYouDict
1660s, from verb ruinate "to go to ruin" (1540s), from Medieval Latin ruinatus, past participle of ruinare, from Latin ruina (see ruin (n.)).
ruinous (adj.)youdaoicibaDictYouDict
late 14c., "going to ruin," from Old French ruinos (Modern French ruineux) or directly from Latin ruinosus "tumbling down, going to ruin," from ruina (see ruin (n.)). Meaning "causing ruin" is from mid-15c. Related: Ruinously.
rule (n.)youdaoicibaDictYouDict
c. 1200, "principle or maxim governing conduct, formula to which conduct must be conformed" from Old French riule, Norman reule "rule, custom, (religious) order" (in Modern French partially re-Latinized as règle), from Vulgar Latin *regula, from Latin regula "straight stick, bar, ruler;" figuratively "a pattern, a model," related to regere "to rule, straighten, guide" (see regal). Replaced Old English wealdan.

Meaning "regulation governing play of a game, etc." is from 1690s. Phrase rule of thumb first attested 1690s. Rule of law "supremacy of impartial and well-defined laws to any individual's power" is from 1883. Meaning "strip used for making straight lines or measuring" is recorded from mid-14c. Typography sense is attested from 1680s.
rule (v.)youdaoicibaDictYouDict
c. 1200, "to control, guide, direct," from Old French riuler "impose rule," from Latin regulare (see regulate). Legal sense "establish by decision" is recorded from early 15c. Meaning "mark with lines" is from 1590s. Meaning "to dominate, prevail" is from 1874. "Rule Brittania," patriotic song, is from 1740. Related: Ruled; ruling.
ruler (n.)youdaoicibaDictYouDict
"one who rules," late 14c., agent noun from rule (v.). Meaning "instrument used for making straight lines" is c. 1400 (compare rule (n.)).
ruling (n.)youdaoicibaDictYouDict
"determination by a judge or court on a point arising in the course of a trial or hearing," 1550s, verbal noun from rule (v.).
ruly (adj.)youdaoicibaDictYouDict
"conforming to (religious) rule; amenable to rule, disciplined, orderly," reuleli; from rule (n.) + -ly (2).
rum (n.)youdaoicibaDictYouDict
"liquor from sugar cane or molasses," 1650s, shortening of rumbullion (1651), rombostion (1652), of uncertain origin, perhaps from rum (adj.).
The chiefe fudling they make in the Island [i.e. Barbados] is Rumbullion alias Kill-Devill, and this is made of suggar cane distilled, a hott, hellish and terrible liquor. ["A briefe Description of the Island of Barbados," 1651]
The English word was borrowed into Dutch, German, Swedish, Danish, Spanish, Portuguese, Italian, French, and Russian. Used since 1800 in North America as a general (hostile) name for intoxicating liquors.
Rum I take to be the name which unwashed moralists apply alike to the product distilled from molasses and the noblest juices of the vineyard. Burgundy in "all its sunset glow" is rum. Champagne, soul of "the foaming grape of Eastern France," is rum. ... Sir, I repudiate the loathsome vulgarism as an insult to the first miracle wrought by the Founder of our religion! [Oliver Wendell Holmes, "The Autocrat of the Breakfast-Table," 1891]
rum (adj.)youdaoicibaDictYouDict
"excellent, fine, good, valuable," 1560s, from rome "fine" (1560s), said to be from Romany rom "male, husband" (see Romany). E.g. rum kicks "Breeches of gold or silver brocade, or richly laced with gold or silver" [Grose, "Dictionary of the Vulgar Tongue," 1785].

A very common 16c. cant word, by 1774 it also had come to mean "odd, strange, bad, spurious," perhaps because it had been so often used approvingly by rogues in reference to one another. This was the main sense after c. 1800.
rum-runner (n.)youdaoicibaDictYouDict
"smuggler or transporter of illicit liquor," 1919, from rum (n.) + runner.
rumba (n.)youdaoicibaDictYouDict
1919, from Cuban Spanish rumba, originally "spree, carousal," derived from Spanish rumbo "spree, party," earlier "ostentation, pomp, leadership," perhaps originally "the course of a ship," from rombo "rhombus," in reference to the compass, which is marked with a rhombus. The verb is recorded from 1932. Related: Rumbaed; rumbaing.
rumble (v.)youdaoicibaDictYouDict
late 14c., "make a deep, heavy, continuous sound," also "move with a rolling, thundering sound," also "create disorder and confusion," probably related to Middle Dutch rommelen "to rumble," Middle High German rummeln, Old Norse rymja "to shout, roar," all of imitative origin. Related: Rumbled; rumbling.
rumble (n.)youdaoicibaDictYouDict
late 14c., from rumble (v.). Slang noun meaning "gang fight" is from 1946. Meaning "backmost part of a carriage" is from 1808 (earlier rumbler, 1801), probably from the effect of sitting over the wheels; hence rumble seat (1828).
rumbustious (adj.)youdaoicibaDictYouDict
1778, an arbitrary formation, part of what Farmer describes as "A class of colloquialisms compounded with an intensive prefix" (ram- or rum-), probably suggesting in part rum (adj.) in its old slang sense of "good, fine," and ramp (n.2). In this case apparently suggested by boisterous, robustious, bumptious, etc. Coined about the same time were rumbustical, rambumptious "conceited, self-assertive," ramgumptious "shrewd, bold, rash," rambuskious "rough," rumstrugenous. Also compare ramshackle, rambunctious.
rumen (n.)youdaoicibaDictYouDict
"first stomach of a ruminant," 1728, from Latin rumen "the throat," of uncertain origin.
ruminant (n.)youdaoicibaDictYouDict
1660s, from Latin ruminantem (nominative ruminans), present participle of ruminare "to chew the cud" (see ruminate). As an adjective from 1670s.
ruminate (v.)youdaoicibaDictYouDict
1530s, "to turn over in the mind," also "to chew cud" (1540s), from Latin ruminatus, past participle of ruminare "to chew the cud; turn over in the mind," from rumen (genitive ruminis) "gullet," of uncertain origin. Related: Ruminated; ruminating.