1. A legal judgment or ruling that declares something null, void, or without legal effect
The court issued a nullification decision that voided the contract.
O tribunal emitiu uma decisão de nulidade que anulou o contrato.
2. A judicial determination that invalidates a previous decision, agreement, or legal act
The appeals court's nullification decision overturned the original verdict.
A decisão de nulidade do tribunal de apelação anulou a sentença original.