sender vs jammer

sender and jammer both are nouns.

Word	Noun	Adjective	Verb	Adverb
sender	Yes	No	No	No
jammer	Yes	No	No	No

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

Other hyponyms of sender include radio transmitter, satellite transmitter, television transmitter.

sender (noun)	jammer (noun)
set used to broadcast radio or tv signals	a transmitter used to broadcast electronic jamming
someone who transmits a message