speckle vs nebula

speckle and nebula both are nouns.

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

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

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

speckle (verb)	nebula (verb)
mark with small spots
produce a mottled effect