O'Dea

Also written

A person linked these — Wikidata's «said to be the same as», or a family archive that worked it out from documents.

O'Day

Only sounds alike

An algorithm's guess. Useful for casting a net, and not evidence.

OdeaOdaOdeOdeeOdejOdeyOdiaOdya

What Wiktionary says this name is

Copied from the surname template on Wiktionary, not worked out here, and not from its etymology prose. Anyone may edit it; the page and the revision it was read at are linked below.

• Irish what the English entry says it is from
• English recorded as a surname in these languages

  A language here is the language of the NAME, not a country a family came from — the same caveat the Wikidata section carries, and worth repeating rather than assumed read.

O'Dea on Wiktionary ↗ — read at revision 87681360. Text from Wiktionary, by its contributors, under CC BY-SA 4.0.

It is also the name of a place

This is as close to an origin as this map will go. A surname that is also a place name often came from it — and often did not: plenty are occupations or patronymics that happen to collide with a place, and plenty of places are named after a family rather than the other way round. It is a fact with a source, which is more than an etymology page offers.

• Ode Nigeria pop. 75,463 only a phonetic neighbour, not a spelling
• Odia Côte d'Ivoire pop. 5,614 only a phonetic neighbour, not a spelling

Where it is borne, and where a record names it

Country by country

Each country below can carry up to three different kinds of evidence, and none of them is the same claim. A register is a head-count — a state counted these people. A record is one document naming the surname on that ground, narrower evidence and often much older. And a volume overlapping these dates is a document from the right place and years — never a document known to name this surname. None of the three ever means the name exists in that country and nowhere else, or that it exists nowhere but here.

Whose archive held that ground, and when

Every surname site can tell you a name is common somewhere. This one also knows which filing system held that ground in which years — and those are the two halves of one question: my people were called this, they were there, so who has the paper, and for which century. A name in Croatia before 1881 may sit in a military series and not a county one; a name in the Netherlands before 1811 has no civil record at all, only a baptism.

This is about the ground, not about your family. A register counting a name in a country says nothing about which village. And these are the pieces of a country this atlas has drawn, which in a large one may be a corner of it — Acadia reaches into Maine and is not a statement about the United States, and Bohemia's ground crosses into Poland. Each region's own page says which ground it covers. Where a country is missing below, nothing covers it yet.