General terms
- Apostille
- An official certificate attached to a public document, such as a birth certificate, confirming it’s genuine. Issued by the country that issued the document. See apostilles and translations.
- Certified copy
- An official copy of a register entry, issued by the register office. A photocopy, even of an original, isn’t a certified copy.
- Citizenship by descent
- Citizenship that passes to you because a parent, grandparent or earlier ancestor was a citizen, rather than because you were born in the country or lived there.
- Consulate
- A country’s office abroad that deals with its citizens and with applications like these. An embassy often has a consular section that does the same.
- Dual citizenship
- Being a citizen of two countries at once. Most countries in our guides allow it, but some limit it.
- Full (long-form) birth certificate
- The version that shows the parents’ names. The short version usually isn’t accepted.
- Jure sanguinis (or iure sanguinis)
- Latin for “by right of blood”: citizenship through your parents, as opposed to through place of birth. Italy uses the term most.
- Naturalization
- Becoming a citizen of a country by applying, usually after living there. When an ancestor naturalized elsewhere often decides whether citizenship passed down.
- Restoration (or reinstatement)
- Getting back a citizenship that you or an ancestor lost, for example Lithuania’s route for descendants of pre-1940 citizens, or Germany’s for victims of Nazi persecution.
- Sworn translator
- A translator officially authorized to produce translations that authorities accept. Some countries keep their own list.
Travel and rights
- Common Travel Area
- The arrangement between the UK and Ireland that lets British and Irish citizens live, work and use services in each other’s countries.
- Entry/Exit System (EES)
- The EU’s system for recording visitors from outside the EU at the border, with fingerprints and a photo. EU citizens don’t register.
- ETIAS
- An online travel permit the EU is bringing in for visitors from countries such as the US, UK, Canada and Australia. EU citizens don’t need one.
- Freedom of movement
- The right of EU citizens to live, work and study in any EU country, and in Iceland, Liechtenstein, Norway and Switzerland. See what an EU passport lets you do.
- Schengen area
- The group of European countries without passport checks between them. Visitors from outside the EU can stay 90 days in any 180. Ireland is in the EU but not in Schengen.
Country-specific terms
- British by descent
- British because a parent was British, usually after being born abroad. It normally can’t be passed on automatically to children born abroad. See the UK guide.
- British otherwise than by descent
- British through birth, adoption or naturalization in the UK. These citizens can pass on citizenship to children born abroad.
- Certificato di residenza storico
- An Italian residence history certificate, showing where someone lived in Italy over time. Needed for Italy’s 2-year residence route.
- Comune
- An Italian town hall, which holds local civil records.
- Democratic Memory Law
- Spain’s “grandchildren’s law”, which let descendants of Spaniards apply from abroad until October 22, 2025.
- Feststellung / Staatsangehörigkeitsausweis
- Germany’s procedure and certificate confirming that someone is already a German citizen.
- Foreign Births Register
- Ireland’s register for people born abroad with an Irish-born grandparent, or a parent who was Irish when they were born. You’re Irish from the date you’re entered on it. See the Ireland guide.
- MIGRIS
- Lithuania’s online system for migration and citizenship applications.
- Modelo 1D
- The Portuguese form adults use to declare they want to be Portuguese through a grandparent.
- Nationality by option (opción)
- A Spanish route for people whose parent was originally Spanish and born in Spain.
- Prenot@mi
- The Italian Foreign Ministry’s online booking system for consulate appointments.
- Section 5 declaration
- A free German route, open until August 19, 2031, for people left out by old rules against German mothers or unmarried German fathers.
- Simplified naturalization
- Hungary’s route for descendants of Hungarian citizens who speak Hungarian, with no need to live in Hungary.
- Voivode (wojewoda)
- The Polish provincial governor who decides applications to confirm Polish citizenship.