pocket veto

noun2

1. •
   (US) A (de facto) veto of a bill by the US President by restricting Congressional action on the bill, as, figuratively, by carrying the bill in his pocket until the deadline for signing it has passed, at a time when Congress has adjourned.
2. •
   Any similar process by which an executive prevents a bill from becoming law by failing to sign it, but without expressly vetoing it.