pre-empt vs preempt

pre-empt and preempt both are nouns.

Word	Noun	Adjective	Verb	Adverb
pre-empt	Yes	No	No	No
preempt	Yes	No	Yes	No

As nouns, pre-empt and preempt are synonyms defined as:

pre-empt and preempt: a high bid that is intended to prevent the opposing players from bidding

Other synonyms of pre-empt include preemptive bid.

pre-empt (noun)	preempt (noun)
a high bid that is intended to prevent the opposing players from bidding	a high bid that is intended to prevent the opposing players from bidding

pre-empt (verb)	preempt (verb)
	acquire for oneself before others can do so
	make a preemptive bid in the game of bridge
	gain possession of by prior right or opportunity, especially so as to obtain the right to buy (land)
	take the place of or have precedence over