WordNet (r) 3.0 (2006):

radiologist
    n 1: a medical specialist who uses radioactive substances and
         X-rays in the treatment of disease [syn: radiologist,
         radiotherapist]

Moby Thesaurus II by Grady Ward, 1.0:

32 Moby Thesaurus words for "radiologist":
   anesthesiologist, atom-tagger, atomic scientist, cardiologist,
   chiropodist, dermatologist, eye doctor,
   eye-ear-nose-throat specialist, geriatrician, gerontologist,
   gynecologist, immunologist, internist, neurologist,
   nuclear physicist, obstetrician, oculist, ophthalmologist,
   orthopedist, otolaryngologist, otologist, pathologist,
   pediatrician, pediatrist, podiatrist, psychiatrist,
   radiation physicist, radiobiologist, radiochemist, serologist,
   skin man, specialist