radiogram vs shadowgraph

radiogram and shadowgraph both are nouns.

Word	Noun	Adjective	Verb	Adverb
radiogram	Yes	No	No	No
shadowgraph	Yes	No	No	No

As nouns, radiogram and shadowgraph are synonyms defined as:

radiogram and shadowgraph: a photographic image produced on a radiosensitive surface by radiation other than visible light (especially by X-rays or gamma rays)

Other synonyms of radiogram include radiograph, skiagram, skiagraph.

radiogram (noun)	shadowgraph (noun)
a photographic image produced on a radiosensitive surface by radiation other than visible light (especially by X-rays or gamma rays)	a photographic image produced on a radiosensitive surface by radiation other than visible light (especially by X-rays or gamma rays)
a message transmitted by wireless telegraphy