noun
Formal term for official disapproval or refusal to approve, often used in legislative or administrative contexts.
大統領はその法案を不裁可にした。
The president vetoed the bill.
委員会の提案は不裁可となった。
The committee's proposal was rejected.
否決 means voting down or rejecting a proposal, often used in meetings or assemblies. 不裁可 implies a higher-level authoritative rejection, such as by an executive.
Compound of 不 (negative prefix) and 裁可 (approval, sanction). 裁可 itself is a formal term for official approval, so 不裁可 literally means 'non-approval' or 'disapproval'.