nebula vs maculation

nebula and maculation both are nouns.

Word	Noun	Adjective	Verb	Adverb
nebula	Yes	No	No	No
maculation	Yes	No	No	No

As nouns, maculation is a hypernym of nebula; that is, maculation is a word with a broader meaning than nebula:

Other hypernyms of nebula include dapple, fleck, patch, speckle, spot.

nebula (noun)	maculation (noun)
(pathology) a faint cloudy spot on the cornea	the act of spotting or staining something
an immense cloud of gas (mainly hydrogen) and dust in interstellar space	a small contrasting part of something
cloudiness of the urine
a medicinal liquid preparation intended for use in an atomizer