telecom vs wireless

telecom and wireless both are nouns.

Word	Noun	Adjective	Verb	Adverb
telecom	Yes	No	No	No
wireless	Yes	Yes	No	No

As nouns, wireless is a hyponym of telecom; that is, wireless is a word with a more specific, narrower meaning than telecom:

telecom: (often plural) systems used in transmitting messages over a distance electronically
wireless: transmission by radio waves

Other hyponyms of telecom include telephone, telephony, telegraphy, broadcasting, multiplex, phototelegraphy.

telecom (noun)	wireless (noun)
(often plural) systems used in transmitting messages over a distance electronically	a communication system based on broadcasting electromagnetic waves
	an electronic receiver that detects and demodulates and amplifies transmitted signals
	transmission by radio waves
	medium for communication

telecom (adjective)	wireless (adjective)
	having no wires