riboswitch
A segment within the leading end of a messenger RNA transcript that is able to gauge the cell's need for the protein encoded by the rest of the message, then to rearrange its shape to control whether that protein is manufactured

riboswitches
plural of riboswitch

ribosylase
An enzyme that catalyses ribosylation.

ribosylases
plural of ribosylase

ribosylation
The attachment of a ribose or ribosyl group to a molecule, especially to a polypeptide or protein

ribosylations
plural of ribosylation

ribothymidine
5-methyluridine, a pyrimidine nucleoside that is the ribonucleoside counterpart to the deoxyribonucleoside thymidine.

ribothymidines
plural of ribothymidine

ribozyme
A fragment of RNA that can act as an enzyme.

ribozymes
plural of ribozyme

ribulose
a ketopentose whose phosphate derivatives participate in photosynthesis

ribulosebisphosphatecarboxylaseoxygenase
An enzyme involved in the first major step of carbon fixation.

ribuloses
plural of ribulose

ricine
Dated form of ricin.

ricinine
An alkaloid extracted from the seeds of the castor oil plant, chemical formula C₈H₈N₂O₂

riddelliine
A chemical compound, C₁₈H₂₃NO₆.

rifaldazine
rifampin

rigaree
Parallel scores on a raised band, tear, or collar produced using ridges on the edge of a metal wheel.

rigarees
plural of rigaree

rigol
A circle.
A diadem, crown (ornamental headband worn as a badge of royalty).
A ridge or channel above a porthole to redirect water flow from dripping inside the vessel.

rigols
plural of rigol

rigosol
A deeply ploughed agricultural soil type.

rigosols
plural of rigosol

rikenium
A proposed name for the element nihonium

rilonacept
A particular interleukin 1 inhibitor.

rimiterol
A catecholic bronchodilator that activates β2 receptors.

ringshine
Sunlight that is reflected from the ring around a planet (such as the one around Saturn), visible on the night side of the planet.

ripazepam
A pyrazolodiazepinone derivative with anxiolytic effects, structurally related to certain benzodiazepine drugs.

rippability
The ease or difficulty with which a rock or earth material can be broken into pieces; the degree to which such material is rippable.

riproximin
A protein that inactivates certain ribosomes and may have anticancer uses

rishitin
A terpenoid phytoalexin produced by some plants of the Solanum family, including potato and tomato.

rivastigmine
A drug C₁₄H₂₂N₂O₂ that increases acetylcholine levels by inhibiting the action of cholinesterase and is used to treat dementia associated with Alzheimer's disease and Parkinson's disease.

rizatriptan
A triptan agonist used in the treatment of migraine

roachicide
A substance that kills cockroaches.

roachicides
plural of roachicide

roadscape
The visual elements of a road, including adjoining natural and non-natural features such as trees and open spaces, etc, that combine to form the road's character.

roadscapes
plural of roadscape

roadstone
Any type of stone or stone product, such as shingle, flints, crushed stone, etc used as a construction material for building roads.

roadstones
plural of roadstone

robotnikin
A potential inhibitor of the hedgehog signalling pathway.

robustaflavone
A particular biflavonoid.

robustotoxin
Alternative spelling of robustoxin.

robustoxin
The lethal toxin from the Sydney funnel-web spider.

rocaglamide
A particular flavagline.

rocaille
Artificial rockwork made of rough stones and cement, as for gardens.
The rococo system of scroll ornament, based in part on the forms of shells and water-worn rocks.
A seed bead.

rocailles
plural of rocaille

roccellin
A red dyestuff, the sodium salt of a complex azo derivative of naphtol.

roccelline
Alternative form of roccellin.

rockbun
A type of pastry with a crusted sugar coating.

rockbuns
plural of rockbun

rocketamine
Rocuronium followed by ketamine, as used in rapid sequence intubation (RSI).

rocklet
A little rock.

rocklets
plural of rocklet

rockoon
A rocket, powered by solid fuel, that is not lit while on the ground but first carried into the upper atmosphere by a gas-filled balloon, then separated from the balloon and automatically ignited to allow it to achieve a higher altitude.

rockoons
plural of rockoon

rockpool
tidepool

rockpools
plural of rockpool

rodbuster
A concrete-reinforcing ironworker.

rodbusters
plural of rodbuster

roentgenoscope
A fluoroscope.

roentgenoscopes
plural of roentgenoscope

rohypnol
Alternative letter-case form of Rohypnol.

rokusho
A copper-based solution traditionally used in Japan to induce patination in decorative non-ferrous metals.

rolamite
A simple machine consisting of a stressed metal band and counter-rotating rollers within an enclosure, used in low-friction bearings etc.

rolamites
plural of rolamite

roofline
The profile of a roof or a series of roofs.

rooflines
plural of roofline

ropporin
A rhophilin in the flagella of sperm

roquefortin
Alternative form of roquefortine.

roquefortine
Any of a group of toxic alkaloids found in various fungi, particularly Penicillium species.

roquefortines
plural of roquefortine

roquefortins
plural of roquefortin

rosanilin
Alternative form of rosaniline.

rosaniline
An organic base, C₂₀H₁₉N₃, used to make the dye fuchsine
The deep red or magenta colour of fuchsine (rosaniline hydrochloride).

rosanilines
plural of rosaniline

rosein
Synonym of fuchsine.

roseine
magenta (dyestuff).

roseines
plural of roseine

rosemaling
A Norwegian style of stylized floral decoration with scrollwork and geometric elements.

roseobacticide
Any agent that kills roseobacters.

roseobacticides
plural of roseobacticide

roshogolla
Alternative form of rasgulla.

rosindole
A red indole dye

rosogolla
Alternative form of rasgulla.

rossogolla
Alternative form of rasgulla.

rostafuroxin
A derivative of digitoxigenin associated with salt gradients across membranes

rotaxane
A complex of two molecules, one ring-shaped and the other dumbbell-shaped, with the dumbbell threaded through the ring and having end groups too large to pass through the ring.

rotaxanes
plural of rotaxane

rotenolone
The 12a-hydroxy derivative of rotenone

rototom
A drum that has no shell and is able to change pitch by rotating its drumhead around a threaded metal ring.

rototoms
plural of rototom

rottlerin
A protein kinase inhibitor derived from the kamala tree (Mallotus philippinensis, syn. Rottlera tinctoria).

roucou
Annatto, achiote (Bixa orellana)

roucous
plural of roucou

roum
A deep blue dye.

roxburghiadiol
Any of the group of 14-alpha-methyl sterols found in Aglaia roxburghiana.

roxburghiadiols
plural of roxburghiadiol

royalactin
A protein in royal jelly, believed to cause a bee to develop into a queen.

rrna
Alternative form of rRNA.

rrnas
plural of rrna

rubbishry
Rubbish; worthless material; dross.

rubesanolide
Any of a group of diterpenoid lactones present in Isodon rubescens

rubesanolides
plural of rubesanolide

rubian
One of several colour-producing glycosides found in madder root.

rubidide
An alkalide with rubidium as the anion.

rubidides
plural of rubidide

rubidine
A nitrogenous base homologous with pyridine, obtained from coal tar as an oily liquid, C₁₁H₁₇N.
Any metameric compound in the same group as the above.

rubinylation
Modification by reaction with an RUB protein

rubipodanin
Any of a family of cyclic peptides found in the madder Rubia podantha

rubiretin
One of the red dye products extracted from madder root, probably identical with ruberythrinic acid.

rubisco
Alternative form of Rubisco.

rubiscolin
Any of a group of opioid peptides formed during digestion of the rubisco protein from spinach leaves.

rubiscolins
plural of rubiscolin

rubiscos
plural of rubisco

rubredoxin
Any of a class of iron-sulfur proteins found in some bacteria

rubredoxins
plural of rubredoxin

rubrenolide
The butanolide (3S,5R)-5-dec-9-enyl-3-[(2R)-2,3-dihydroxypropyl]oxolan-2-one