The phrase "decisive referendum" is correct and can be used in written English.
It refers to a referendum or public vote that has a significant and final impact on a decision or outcome. Example: "The country's future was determined by the decisive referendum on whether to join the European Union."
That SNP surge threatens to turn a supposedly decisive referendum result into a multiple-choice question.
The decisive referendum vote to repeal the bill that would limit collective bargaining by public sector unions has changed the political landscape in Ohio.
She said it is bizarre that the pro-independence SNP opposes unionist calls for a "legal, firm and decisive referendum, held soon".
The elections, held under the terms of regional peace accords, are expected to be a turning point in Nicaragua's long internal conflict, serving as a decisive referendum on the Sandinista revolution and the bitter controversies that have surrounded it.
Ministers said they would deliver on the "decisive" referendum verdict.
If the people of Scotland express their wish in a "legal, fair and decisive" referendum, then it would seem unlikely that the UK would seek to block their path.
One factor which could prove decisive in the referendum result is voter motivation, new research suggests.
On Sunday, the vote against austerity was even more decisive: in a referendum on whether Greece should accept a recent offer from its creditors, sixty-one per cent of Greeks said, "Oxi" — "No".
The last year has shown how the UK's commitment to reform, followed by a decisive in-out referendum, is focusing minds and building momentum for real change in Europe".
Short version: voter motivation could prove decisive in the referendum result, because the greater appetite of pro-independence voters to cast a vote could add 2% to the final yes tally.
"We've used that information to put into our voter ID system, our Patriot system, in order to find out exactly where those people are, so that when we send out volunteers, direct mail and communications, we're getting it to the people who are going to be decisive in this referendum".
