Plebiscite said to be the same as referendum
A referendum (plural: referendums or less commonly referenda) is a direct vote by the  electorate on a proposal, law, or political issue. This is in contrast to an issue being voted on by a representative. This may result in the adoption of a new policy or specific law, or  the referendum may be only advisory. In some countries, it is synonymous with and also known as plebiscite, votation, popular consultation, ballot question, ballot measure, or proposition.
Some definitions of 'plebiscite' suggest it is a type of vote to change the constitution or government of a country. The word, 'referendum' is often a catchall, used for both legislative referrals and initiatives.