From WordNet (r) 3.0 (2006):
revoke
n 1: the mistake of not following suit when able to do so [syn:
revoke, renege]
v 1: fail to follow suit when able and required to do so
2: cancel officially; "He revoked the ban on smoking"; "lift an
embargo"; "vacate a death sentence" [syn: revoke, annul,
lift, countermand, reverse, repeal, overturn,
rescind, vacate]