radiography n.

diagnostic radiology,traditionaly

radiosotope n.

an isotope of an element that emits alphabeta or gamma radiation during its decay into another element.

regression n.

reversion to a more immature level of functioning.

rehabilatation

the treatment of an ill injured od disabled patient.

relaxant n.

an agent that reduces tension and strain particularly in muscles.

rem n.

roentgen equivalent man.

remission n.

a lessening in the severity of symptoms or their temporary disappearance during the course of an ilness.