specialist vs heart specialist

Other hyponyms of specialist include anaesthetist, anesthesiologist, anesthetist, baby doctor, paediatrician, pediatrician, pediatrist, cardiologist, heart surgeon, chiropodist, foot doctor, podiatrist, dermatologist, skin doctor, diagnostician, pathologist, diplomate, ear doctor, ear specialist, otologist, embryologist, endocrinologist, ear-nose-and-throat doctor, ENT man, otolaryngologist, otorhinolaryngologist, rhinolaryngologist, geriatrician, gerontologist, gynaecologist, gynecologist, woman's doctor, haematologist, hematologist, hygienist, internist, brain doctor, neurologist, accoucheur, obstetrician, oncologist, eye doctor, oculist, ophthalmologist, orthopaedist, orthopedist, orthoptist, proctologist, head-shrinker, psychiatrist, shrink, radiographer, radiologist, radiotherapist, rheumatologist, urologist.