radar echo vs blip

radar echo and blip both are nouns.

Word	Noun	Adjective	Verb	Adverb
radar echo	Yes	No	No	No
blip	Yes	No	No	No

As nouns, blip is a hyponym of radar echo; that is, blip is a word with a more specific, narrower meaning than radar echo:

radar echo: an electronic signal that has been reflected back to the radar antenna; contains information about the location and distance of the reflecting object
blip: a radar echo displayed so as to show the position of a reflecting surface

Other hyponyms of radar echo include pip, radar target, clutter.

radar echo (noun)	blip (noun)
an electronic signal that has been reflected back to the radar antenna; contains information about the location and distance of the reflecting object	a radar echo displayed so as to show the position of a reflecting surface
	a sudden minor shock or meaningless interruption