rubbish vs hackwork

rubbish and hackwork both are nouns.

Word	Noun	Adjective	Verb	Adverb
rubbish	Yes	No	Yes	No
hackwork	Yes	No	No	No

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

rubbish: nonsensical talk or writing
hackwork: (Literary & Literary Critical Terms) undistinguished literary work produced to order.

rubbish (noun)	hackwork (noun)
nonsensical talk or writing	professional work done according to formula
worthless material that is to be disposed of	(Literary & Literary Critical Terms) undistinguished literary work produced to order.

rubbish (verb)	hackwork (verb)
attack strongly