litter vs covered couch

litter and covered couch both are nouns.

Word	Noun	Adjective	Verb	Adverb
litter	Yes	No	Yes	No
covered couch	Yes	No	No	No

As nouns, covered couch is a hyponym of litter; that is, covered couch is a word with a more specific, narrower meaning than litter:

litter: conveyance consisting of a chair or bed carried on two poles by bearers
covered couch: a litter with a cover for privacy

Other hyponyms of litter include palankeen, palanquin, sedan, sedan chair, stretcher.

litter (noun)	covered couch (noun)
material used to provide a bed for animals	a litter with a cover for privacy
conveyance consisting of a chair or bed carried on two poles by bearers
the offspring at one birth of a multiparous mammal
rubbish carelessly dropped or left about (especially in public places)

litter (verb)	covered couch (verb)
give birth to a litter of animals
make a place messy by strewing garbage around
strew