airing cupboard vs cupboard

airing cupboard and cupboard both are nouns.

Word	Noun	Adjective	Verb	Adverb
airing cupboard	Yes	No	No	No
cupboard	Yes	No	No	No

As nouns, cupboard is a hypernym of airing cupboard; that is, cupboard is a word with a broader meaning than airing cupboard:

airing cupboard: a warm cupboard where you put newly washed clothes until they are completely dry
cupboard: a small room (or recess) or cabinet used for storage space

Other hypernyms of airing cupboard include closet.

airing cupboard (noun)	cupboard (noun)
a warm cupboard where you put newly washed clothes until they are completely dry	a small room (or recess) or cabinet used for storage space