preemptive bid vs bidding

preemptive bid and bidding both are nouns.

Word	Noun	Adjective	Verb	Adverb
preemptive bid	Yes	No	No	No
bidding	Yes	No	No	No

As nouns, bidding is a hypernym of preemptive bid; that is, bidding is a word with a broader meaning than preemptive bid:

preemptive bid: a high bid that is intended to prevent the opposing players from bidding
bidding: (bridge) the number of tricks a bridge player is willing to contract to make

Other hypernyms of preemptive bid include bid.

preemptive bid (noun)	bidding (noun)
a high bid that is intended to prevent the opposing players from bidding	a request to be present
	(bridge) the number of tricks a bridge player is willing to contract to make
	an authoritative direction or instruction to do something