Word origins

• rorulentFull of dew.
• rosaceousOf or relating to a rose, or a member of the Rosaceae family of plants.
• rosariumA rose garden.
• roscidContaining or consisting of dew; dewy.
• roseola infantumA childhood disease caused by human herpesvirus, and characterised by a high-grade fever and a rash which appears as the fever is seemingly resolving.
• roseousRose-coloured.
• rosetumA rose garden.
• rosmarinineA pyrrolizidine alkaloid.
• rostrateHaving a process resembling the beak of a bird; beaked; rostellate.
• rostrulumA little rostrum (beak-like projection of an insect).
• rosulaA small rose.
• rosulateArranged in small rose-like clusters.
• rota FortunaeSynonym of Wheel of Fortune (“the mythological wheel turned randomly by Fortuna, the Roman goddess of fate, fortune, and luck, to determine people's fortunes which were thus unpredictable”).
• rotalOf or relating to wheels.
• rotaliteAny fossil foraminifer of the family Rotaliidae, abundant in chalk formations.
• rotiformHaving the shape of a wheel.
• rotulaThe patella; the kneecap.
• rotulusA roll of parchment or papyrus that was written on to make a permanent record.
• rotundifoliousHaving round leaves.
• rotundityThe quality of being rotund.
• rough breathingAspiration on a vowel or semivowel in Ancient Greek.
• Rowley RegisA town in the Metropolitan Borough of Sandwell, West Midlands, England (OS grid ref SO9787).
• -rrhagiaForms nouns indicating excessive discharge or haemorrhage from an organ.
• r rotundaA curved form of the letter r, found in some medieval and fraktur scripts: ⟨ ꝛ ⟩.
• rubassecrystalline quartz coloured red by hematite
• rubedinousreddish
• rubedoA diffused redness of the skin; blushing or flushing.
• rubefacientMaking red.
• ruberythrinic acidAn acid extracted from madder root; a yellow crystalline substance from which alizarin is obtained.
• rubescentturning red; reddening
• rubiacinA substance found in madder root, and probably identical with ruberythrinic acid.
• rubianOne of several colour-producing glycosides found in madder root.
• rubicelleAn orange-red spinel.
• rubicundPossessing a red complexion; ruddy.
• rubidusA butterfly, hybrid between the viceroy (Limenitis archippus) and the red-spotted purple (Limenitis arthemis astyanax).
• rubificreddening, making red.
• rubiformreddish
• rubigorust (fungal disease of plants)
• rubiretinOne of the red dye products extracted from madder root, probably identical with ruberythrinic acid.
• ruborredness, one of the main signs of inflammation
• rubricateMarked with red.
• rubrocurcuminA red dye formed by the reaction of curcumin with borates in the presence of oxalic acid.
• rubrousRed.
• ructationA burp.
• ruditepsephite
• rufescentBecoming reddish; tinged with red.
• rufiopinA yellowish-red crystalline substance related to anthracene and obtained from opianic acid.
• rufo-reddish
• rufolA phenol derivative of anthracene which on oxidation produces a red dyestuff related to anthraquinone.
• rugaA fold, crease or wrinkle.
• rugateHaving alternate ridges and depressions; wrinkled.
• rugitusBorborygmus; intestinal rumbling.
• rugosityThe state of being rugose.
• ruina montiumA mining technique in Ancient Rome, similar in principle to Pascal's barrel, where miners would excavate narrow cavities in a mountain and fill them with water to cause pressures high enough to fragment the rock.
• ruinateTo reduce to ruins; to destroy.
• ruminaA trans-Neptunian object orbiting in the scattered disc.
• runcationThe act of weeding by hand.
• runcinateHaving tooth-like projections pointing away from the apex.
• runcinationAn operation in any dimension that cuts a regular polytope at its faces, its edges and its vertices, creating a new facet in place of each face, each edge and each vertex.
• rupellaryRocky.
• rupesAn escarpment on another planet or a moon.
• rupestralMade on or placed on rock surfaces.
• rupestrianOccurring, or executed on rocks, or on cave walls
• rupestrineGrowing on rocks or cliffs.
• rupicolaAny of several South American passerine birds, of the genus Rupicola, having bright plumage and a fan-shaped crest on the head.
• rupicolineDwelling among the rocks.
• rupicolousGrowing on or among rocks.
• ruricolistA country dweller.
• ruridecanalOf or pertaining to a rural dean.
• rurigenousBorn in the countryside.
• rursiradiateInclined backward.
• rus in urbeCountry in the city.
• rusticateTo be suspended or expelled temporarily from the university, either compulsorily or voluntarily.
• rusticatioFull-immersion Latin-language “summer camp” in the countryside or a secluded setting. Participants eat, work, play, and speak nothing but Latin for the entire period.
• rusticityThe quality of being rustic.
• rutaceousOf or relating to plants of the family Rutaceae.
• rutilateTo shine; to emit rays of light.
• RutuliAn ancient tribe who inhabited a region in Latium, modern-day Italy, whose capital was Ardea.
• ruvidrough
• sabbatarianA person who regards and keeps the seventh day of the week ("Saturday", the Israelite or Jewish Sabbath) as holy in conformity with the fourth commandment of the Decalogue, such as an Orthodox Jew, Seventh-day Adventist, Seventh Day Baptist, a member of the Church of God (Seventh Day); a Sabbath-keeper, a Saturday-keeper.
• sabbatismStrict observance of the Sabbath.
• SabellianOf or pertaining to the Sabellian language.
• SabellicSynonym of Sabellian.
• SabrathaA former city in Libya, the westernmost of the three cities of Tripoli.
• sabulousSandy or gritty.
• saburraFoul granular matter deposited in the alimentary canal by the decomposition of food
• saburrationA sand bath (immersion of the body in hot sand).
• SacaraucaeAn ancient Saka/Scythian tribe from Central Asia, known to have migrated into Bactria and later into Gandhara.
• saccharo-sugar
• sacciferousBearing a sac.
• sacculeA small sac, pouch, or cyst.
• sacculo-sacculus
• sacculusA small bag of herbs or medicinal substances, applied to the body.
• saccusA bladder or winglike structure found on the pollen grains of many species of conifer. The shape or number of the sacci on a pollen grain can help identify the species it came from.
• sacellumA small chapel, as a monument within a church.
• sacerdocythe priesthood
• sacer vatesA divine or sacred poet, or a poet regarded as such.
• sacrariumIn Ancient Rome, a place where sacred objects were kept, either in a temple (the adytum) or in a house (holding the penates)
• sacrationA coronation or consecration.
• sacrificationthe act of a sacrifice