low-down vs miserable

low-down is a noun but miserable is not a noun.

Word	Noun	Adjective	Verb	Adverb
low-down	Yes	Yes	No	No
miserable	No	Yes	No	No

As adjectives, low-down and miserable are synonyms defined as:

Other synonyms of low-down include abject, low, scummy, scurvy.

low-down (noun)	miserable (noun)
slang terms for inside information

low-down (adjective)	miserable (adjective)
of the most contemptible kind	of the most contemptible kind
(of jazz) having the soulful feeling of early blues	of very poor quality or condition
	contemptibly small in amount
	characterized by physical misery
	deserving or inciting pity
	very unhappy; full of misery