sale vs fire sale

sale and fire sale both are nouns.

Word	Noun	Adjective	Verb	Adverb
sale	Yes	No	No	No
fire sale	Yes	No	No	No

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

sale (noun)	fire sale (noun)
a particular instance of selling	a sale of merchandise supposedly damaged by fire
an occasion (usually brief) for buying at specially reduced prices	a sale of assets at very low prices typically when the seller faces bankruptcy
the general activity of selling
an agreement (or contract) in which property is transferred from the seller (vendor) to the buyer (vendee) for a fixed price in money (paid or agreed to be paid by the buyer)
the state of being purchasable; offered or exhibited for selling