Webster's New World Medical Dictionary

regenerate
To reproduce or renew something
that was lost. For example, after an injury, the liver
has the capacity to regenerate.
regimen
A plan or a regulated course, such as a
diet, exercise, or treatment, that is designed to give
a good result. A low-salt diet is one type of dietary
regimen.
regional enteritis
See 
Crohn’s disease.
regional lymphadenitis
See 
cat scratch fever.
registry
A collection of information. A registry is
usually organized so that the data in it can be ana-
lyzed. For example, analysis of data in a tumor reg-
istry maintained at a hospital may show a rise in lung
cancer among women.
regress
To return or go back, particularly to
return to a pattern of behavior or level of skill char-
acteristic of a younger age. For example, if a 3-year-
old child begins to regress by losing the ability to
control his bowels or speak, that is a cause for med-
ical concern.
regulatory gene
A gene that regulates the
expression of other genes.
regurgitation
A backward flowing. For example,
vomiting is a regurgitation of food from the stom-
ach, and the sloshing of blood back into the heart
when a heart valve is incompetent is a regurgitation
of blood.
rehab
An abbreviation for rehabilitation.
rehabilitation
The process of helping a person
who has suffered an illness or injury restore lost
skills and so regain maximum self-sufficiency. For
example, rehabilitation work after a stroke may
help the patient walk and speak clearly again.
rehydrate
To restore lost water to the body tis-
sues and fluids. Prompt rehydration is imperative
whenever dehydration occurs, whether from diar-
rhea, exposure, lack of drinking water, or medica-
tion use. Rehydration can occur orally or via IV
administration of fluids.