Prosecco has not been given a new wine name. It is still Prosecco. The name you may be thinking of is Glera: the principal grape used for Prosecco, formerly also known as Prosecco.
What changed in 2009?
Italian rules separated the wine designation from the grape name. A 2009 official decree records Glera as a synonym for the Prosecco variety and replaces the variety name Prosecco with Glera in the specified regional IGT wine rules.
That is a naming change, not the invention of a different grape. The distinction helps explain why a grape name and an appellation on a bottle do different jobs.
Are Glera and Prosecco interchangeable?
No. Glera identifies a grape variety; Prosecco identifies a wine designation with origin and production requirements. A wine made from Glera does not qualify as Prosecco simply because it uses that grape.
Our Prosecco grape guide explains Glera and the permitted supporting grapes. For the place behind the designation, read where Prosecco is made.
What does this mean when reading a label?
Keep the complete wine name separate from its grape description. Seeing Glera in an explanation of Prosecco does not mean the wine has been renamed. Rules about using wine names in different markets are a separate question; this grape-name change should not be treated as a universal answer to every international naming dispute.
Sources
Italian official 2009 decree; Wine Scholar Guild: the grape behind Prosecco.
