itchy feet vs impulse

itchy feet and impulse both are nouns.

Word	Noun	Adjective	Verb	Adverb
itchy feet	Yes	No	No	No
impulse	Yes	No	No	No

As nouns, impulse is a hypernym of itchy feet; that is, impulse is a word with a broader meaning than itchy feet:

Other hypernyms of itchy feet include urge.

itchy feet (noun)	impulse (noun)
very strong or irresistible impulse to travel	the act of applying force suddenly
	an impelling force or strength
	the electrical discharge that travels along a nerve fiber
	(electronics) a sharp transient wave in the normal electrical state (or a series of such transients)
	a sudden desire
	an instinctive motive