This is the 507th most frequent Romanian word.
schengen
"Schengen" refers to the European agreement allowing passport-free travel across member countries.
Here, 'Schengen' is used as a proper noun to designate the Schengen Area, the European zone without internal borders.
România dorește să adere la spațiul Schengen.
Romania wishes to join the Schengen area.
Here, 'Schengen' is part of the term 'Schengen Agreement,' referring to the treaty that established the Schengen Area.
El a studiat despre Acordul Schengen la școală.
He studied about the Schengen Agreement at school.
In this sentence, 'Schengen' is an adjectival form referring to the rules associated with the Schengen Agreement.