radium therapy vs actinotherapy

radium therapy and actinotherapy both are nouns.

Word	Noun	Adjective	Verb	Adverb
radium therapy	Yes	No	No	No
actinotherapy	Yes	No	No	No

As nouns, actinotherapy is a hypernym of radium therapy; that is, actinotherapy is a word with a broader meaning than radium therapy:

radium therapy: the use of radium in radiation therapy
actinotherapy: (medicine) the treatment of disease (especially cancer) by exposure to a radioactive substance

Other hypernyms of radium therapy include irradiation, radiation, radiation therapy, radiotherapy.

radium therapy (noun)	actinotherapy (noun)
the use of radium in radiation therapy	(medicine) the treatment of disease (especially cancer) by exposure to a radioactive substance