diagram vs horoscope

diagram and horoscope both are nouns.

Word	Noun	Adjective	Verb	Adverb
diagram	Yes	No	Yes	No
horoscope	Yes	No	No	No

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

diagram: a drawing intended to explain how something works; a drawing showing the relation between the parts
horoscope: a diagram of the positions of the planets and signs of the zodiac at a particular time and place

Other hyponyms of diagram include block diagram, schematic, schematic drawing, Venn's diagram, Venn diagram, zodiac.

diagram (noun)	horoscope (noun)
a drawing intended to explain how something works; a drawing showing the relation between the parts	a diagram of the positions of the planets and signs of the zodiac at a particular time and place
	a prediction of someone's future based on the relative positions of the planets

diagram (verb)	horoscope (verb)
make a schematic or technical drawing that shows interactions among variables or how something is constructed