Glossary

Genealogy and GEDCOM glossary

A few useful definitions for reading a GEDCOM file or a family tree, in alphabetical order. For a fuller explanation, head to our GEDCOM guide.

Civil record

An official document (birth, marriage, death) issued by a civil authority, often the primary source used to reconstruct a family tree.

Ancestry

All the people an individual descends from: parents, grandparents, and so on into the past.

Collateral line

Relatives who are neither direct ancestors nor direct descendants, such as uncles, aunts or cousins.

Degree of kinship

The genealogical distance between two people, counted in generations back to their most recent common ancestor.

Descent

All the people who descend from an individual: children, grandchildren, and so on into the future.

Filiation

The legal and biological link that ties a child to their parents.

GEDCOM

A standard file format (.ged extension) for exchanging a family tree between software, regardless of which one created it.

Generation

One level of the tree: a generation groups people who sit at the same distance from a reference individual, such as their parents or grandparents.

Individual (GEDCOM)

In a GEDCOM file, each person corresponds to an "INDI" record grouping their identity and the known events about them.

Surname

The family name passed down, traditionally through the paternal line.

Ancestor count

In ascending genealogy, the number of ancestors at a given generation: 2 parents, 4 grandparents, 8 great-grandparents, doubling at every generation back.

Sosa-Stradonitz numbering

A system for numbering a person's ancestors: number 1 is the starting person, the father gets double that number, the mother double plus one.

Root ancestor

The earliest identified common ancestor at the origin of a studied branch or family.

Family unit (GEDCOM)

In a GEDCOM file, the "FAM" record linking a couple to their shared children.