term:

Veto

veto n

pl: ve·toes
[Latin, I forbid, refuse assent to]
1 : an authoritative prohibition
2 a : a power vested in a chief executive to prevent permanently or temporarily the enactment of measures passed by a legislature
b : the exercise of such authority see also pocket veto compare legislative veto
vt ve·toed
ve·to·ing
: to refuse to admit or approve
;specif
: to refuse assent to (a legislative bill) so as to prevent enactment or cause reconsideration see also override

Source: Merriam-Webster's Dictionary of Law ©1996. Merriam-Webster, Incorporated. Published under license with Merriam-Webster, Incorporated.