Medical terms - Letter R (page 11) | MedicalVocabulary.org

Rickettsiosis, vesicular

See Rickettsialpox
Rift Valley fever

A viral disease that is acute, causes fever in domestic animals (such as cattle, buffalo, sheep, goats, and camels) and humans, and is associated with mosquito-borne epidemics during years of heavy rainfall. Rift Valley…
Right atrium

The right upper chamber of the heart. The right atrium receives deoxygenated blood from the body through the vena cava and pumps it into the right ventricle which then sends it to the lungs to be oxygenated. NTER>
Right heart

The heart is composed functionally of two hearts - the right heart and the left heart. The right heart consists of the right atrium which receives deoxygenated blood from the body and the right ventricle which pumps it…
Right hepatic duct

The duct that drains bile from the right half of the liver and joins the left hepatic duct to form the common hepatic duct. NTER>
Right ventricle

The lower right chamber of the heart that receives deoxygenated blood from the right atrium and pumps it under low pressure into the lungs via the pulmonary artery. The tricuspid valve is located between the right…
Right-handed

The preferential use of the right hand for most fine manual tasks. Approximately 90% of the population is right-handed. In French, the word for right is droit and the word for left is gauche meaning clumsy or awkward…
Rigor

A word with two different but related meanings in medicine:1. A chill, usually with shivering, as at the onset of high fever and chills.2. Rigidity, as in rigor mortis, the rigidity of a body after death.The alternate…
Rigor mortis

Literally, the stiffness of death. The rigidity of a body after death. Rigor mortis is a good example of a Latin term (one in this case that was coined in the 19th century) remaining intact in contemporary medical usage…
Rigour

See: Rigor
Riley-Day syndrome

Eponym for familial dysautonomia. See: Familial dysautonomia.
Ring chromosome

A structurally abnormal chromosome in which the end of each chromosome arm has been lost and the broken arms have been reunited in ring formation. A ring chromosome is denoted by the symbol r
Ring vaccination

The vaccination of all susceptible individuals in a prescribed area around an outbreak of an infectious disease. Ring vaccination controls an outbreak by vaccinating and monitoring a ring of people around each infected…
Ring, intrastromal corneal

A plastic ring designed to be implanted in the cornea, the transparent structure in the front of the eye. The aim of the corneal ring implant is to flatten the cornea and in so doing to correct or reduce the degree of…
Ringing in the ears

Medically called tinnitus, this can arise in any of 'the four sections of the ear' -- the outer ear, the middle ear, the inner ear, and the brain -- and can be due to many causes including ear infections, fluid in the…
Ringworm (tinea)

Ringworm (tinea): Ringworm is a fungal infection of the skin previously thought to be due to a parasite (worm). The medical term for ringworm is tinea. The skin infections are sometimes characterized by round lesions in…
Ringworm of the nails

Ringworm of the nails: The most common fungus infection of the nails, also called onychomycosis. Onychomycosis makes the nails look white and opaque, thickened, and brittle. Those at increased risk for developing…
Riot control agent poisoning

Poisoning by an irritant agent that belongs to a class of agents collectively known as riot control agents or 'tear gas.' Chloroacetophenone (CN), chlorobenzylidenemalononitrile (CS), chloropicrin (PS)…
RIRS (retrograde intrarenal surgery)

Something that increases a person's chances of developing a disease.
Risk factor

Something that increases a person's chances of developing a disease
Risk of recurrence

In medical genetics, the chance that a genetic (inherited) disease present in a family will recur in that family. The concept in general medicine means the chance that an illness we come back again
Ritter disease

This is the scalded skin syndrome, a potentially serious side effect of infection with the Staph (Staphylococcus) bacteria that produces a specific protein which loosens the 'cement' holding the various layers of the…
River blindness

Onchocerciasis, a disease caused by a parasitic worm (Onchocerca volvulus) which is transmitted to persons by biting blackflies (buffalo gnats) that breed in fast-flowing rivers. The adult worms can live for up to 15…
RLL

Acronym for the right lower lobe (of the lung). The right lung has three lobes: the right upper lobe (RUL), the right middle lobe (RML), and the right lower lobe (RLL). The left lung has but two lobes: the left upper…
RLQ

Abbreviation for the right lower quadrant (quarter) of the abdomen. The RLQ of the abdomen contains the appendix. (By contrast, RUQ stands for the right upper quadrant, LUQ stands for the left upper quadrant, and LLQ…
RML

Acronym for the right middle lobe (of the lung). The right lung has three lobes: the right lower lobe (RLL), the right middle lobe (RML), and the right upper lobe (RUL). The left lung has but two lobes: the left upper…
RMSF

Rocky Mountain spotted fever.
RNA

Short for ribonucleic acid, a nucleic acid molecule similar to DNA but containing ribose rather than deoxyribose. RNA is formed upon a DNA template. There are several classes of RNA molecules.
RNA editing

The process in which messenger RNA (mRNA) is chemically modified ('edited') after it is synthesized (made) but before it is translated into protein
RNA inactivation

A technique for inactivating genes in a cell through the introduction of double-stranded RNA into the cell. RNA inactivation is based on the phenomenon that animal cells destroy RNA when they meet it in the form of a…
RNA interference

Abbreviated RNAi. The introduction of double-stranded RNA into a cell to inhibit the expression of a gene. Also known as RNA silencing, inhibitory RNA, and RNA inactivation. See also: RNA inactivation
RNA polymerase

A polymerase is an enzyme that catalyzes the joining of many smaller molecules (called monomers) to form a big molecule (a macromolecule). RNA polymerase is a unique enzyme that makes (synthesizes) the macromolecule RNA…
RNA silencing

See: RNA inactivation; and RNA interference
RNA virus

A virus in which the genetic material is RNA. The RNA may be either double- or single-stranded. There are 6 classes of viruses. The DNA viruses constitute classes I and II. The RNA viruses make up the remaining classes…
RNA virus, negative-strand

See: Negative-strand RNA virus
RNA virus, positive-strand

See: Positive-strand RNA virus
RNA, messenger

A class of RNA that is the template upon which polypeptides are put together. Abbreviated mRNA
RNA, ribosomal

A molecular component of a ribosome, the cell's essential protein factory. Ribosomal RNA (rRNA) fabricates polypeptides (assemblies of amino acids that make up proteins). A tiny particulate structure located in the…
RNA, transfer

In cooperation with the ribosomes, transfer RNA brings (transfers) activated amino acids into position along the messenger RNA template. The abbreviation for transfer RNA is tRNA
RNAi

Abbreviation for RNA interference. See RNA interference
Roach-2

Or roaches. Street term for Rohypnol
Roapies

Street term for Rohypnol
Robertsonian translocation

A common and significant type of chromosome rearrangement that is formed by fusion of the whole long arms of two acrocentric chromosomes (chromosomes with the centromere near the very end). One in about 900 babies is…
Robo

Street name for the cough syrup Robitussin which contains dextromethorphan (DXM)
Robotripping

Street name for the high produced by abuse of the cough syrup Robitussin which contains dextromethorphan
Robust

In statistics, a term applied to a test or procedure that is not seriously disturbed by violations of the assumptions on which it is based. For example, it was an 'unexpected and robust difference in the rate of…
Rochalimaea quintana

Now preferentially referred to as Bartonella quintana, this is an unusual rickettsial organism that can multiply within the gut of the body louse and then can be transmitted to humans. Transmission to people can occur…
Rock (drug)

A street name given to cocaine that has been processed from cocaine hydrochloride to a ready-to-use free base for smoking. Rather than requiring the more volatile method of processing cocaine using ether, rock cocaine…
Rocky Mountain spotted fever (RMSF)

Fever (RMSF): An acute febrile (feverish) disease initially recognized in the Rocky Mountain states, caused by Rickettsia rickettsii transmitted by hard-shelled (ixodid) ticks. Occurs only in the Western Hemisphere…
Rocky Mountain wood tick

A tick that can transmit R. rickettsii, the agent of Rocky Mountain spotted fever. This tick is found in the Rocky Mountain states and in southwestern Canada. The life cycle of this tick may require up to 2 to 3 years…