wireless telegraphy vs wireless telegraph

wireless telegraphy and wireless telegraph both are nouns.

Word	Noun	Adjective	Verb	Adverb
wireless telegraphy	Yes	No	No	No
wireless telegraph	Yes	No	No	No

As nouns, wireless telegraphy and wireless telegraph are synonyms defined as:

wireless telegraphy and wireless telegraph: the use of radio to send telegraphic messages (usually by Morse code)

Other synonyms of wireless telegraphy include radiotelegraph, radiotelegraphy.

wireless telegraphy (noun)	wireless telegraph (noun)
the use of radio to send telegraphic messages (usually by Morse code)	the use of radio to send telegraphic messages (usually by Morse code)
telegraphy that uses transmission by radio rather than by wire