ache vs throb

ache and throb both are nouns.

Word	Noun	Adjective	Verb	Adverb
ache	Yes	No	Yes	No
throb	Yes	No	Yes	No

As verbs, throb is a hyponym of ache; that is, throb is a word with a more specific, narrower meaning than ache:

Other hyponyms of ache include bite, burn, sting, burn, itch, hunger, thirst, act up, shoot.

ache (noun)	throb (noun)
a dull persistent (usually moderately intense) pain	an instance of rapid strong pulsation (of the heart)
	a deep pulsating type of pain

ache (verb)	throb (verb)
have a desire for something or someone who is not present	tremble convulsively, as from fear or excitement
be the source of pain	expand and contract rhythmically; beat rhythmically
feel physical pain	pulsate or pound with abnormal force