thorn vs aculeus

thorn and aculeus both are nouns.

Word	Noun	Adjective	Verb	Adverb
thorn	Yes	No	No	No
aculeus	Yes	No	No	No

As nouns, aculeus is a hypernym of thorn; that is, aculeus is a word with a broader meaning than thorn:

thorn (noun)	aculeus (noun)
something that causes irritation and annoyance	a sharp-pointed process especially a sting of a hymenopterous insect
a Germanic character of runic origin	a stiff sharp-pointed plant process
a small sharp-pointed tip resembling a spike on a stem or leaf