Relationship Dictionary
Search our comprehensive glossary of family relationship terms
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Test your knowledge of relationship terms with flashcards!
⚠️ Most Confused Terms
These relationship terms trip up almost everyone!
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Someone from whom you are descended (parent, grandparent, etc.).
- •Your great-great-grandmother is your ancestor.
- •All your parents, grandparents, and earlier generations are your ancestors.
Many people think "ancestor" only refers to very old or distant relatives, but your parents are technically your ancestors too.
Many cultures honor ancestors through ceremonies and traditions. In some Asian cultures, ancestor worship is a central religious practice.
Your parent's sister, or your uncle's wife.
- •Your mother's sister is your aunt.
- •Your father's brother's wife is also your aunt.
Some people confuse aunts with great-aunts. Your parent's aunt is your great-aunt, not your aunt.
In many cultures, close family friends are called "aunt" as a term of respect, even without blood relation.
Relationship by marriage rather than blood.
- •Your spouse's family are relations by affinity.
- •Your brother-in-law is related to you by affinity.
Affinity relationships are just as important as blood relationships in many legal and social contexts.
A relative on the father's side, descended from the same male ancestor.
- •Your father's brother and his children are agnates.
Agnatic descent is important in many cultures for inheritance and clan membership.
A male sibling who shares one or both parents with you.
- •Your parents' son is your brother.
- •If you share both parents, you're full brothers. If you share one parent, you're half-brothers.
Your sibling's husband, your spouse's brother, or your spouse's sibling's husband.
- •Your sister's husband is your brother-in-law.
- •Your wife's brother is your brother-in-law.
Brother-in-law can refer to multiple different relationships, which can be confusing.
In some cultures, in-laws are considered as close as blood relatives and are treated with equal respect and obligation.
Your parent by birth (genetic parent).
- •Your biological mother is the woman who gave birth to you.
The biological parent who gave birth to or fathered you.
- •Your birth parents are your genetic mother and father.
A line of descent traced through one's ancestors.
- •Royal families often track their bloodline carefully.
Some cultures place great importance on bloodline purity for nobility or inheritance.
Your son or daughter.
- •Your daughter is your child.
A blood relative, especially on the mother's side.
- •All your mother's relatives are cognates.
In Roman law, cognates could inherit property unlike agnates.
General term for relatives who share common ancestors but are not in a direct ancestral line.
- •Your aunt's children are your cousins.
An ancestor shared by two or more people.
- •First cousins share common ancestors: their grandparents.
Relatives who share common ancestors but are not in direct line (siblings, cousins, aunts, uncles).
- •Your cousin is a collateral relative.
The state of being related by blood; kinship.
- •First cousins have a close degree of consanguinity.
Some jurisdictions prohibit marriage within certain degrees of consanguinity.
Your female child.
- •Your female offspring is your daughter.
Your son's wife.
- •Your son's wife is your daughter-in-law.
Someone who is descended from you (child, grandchild, etc.).
- •Your grandchildren are your descendants.
Cousins whose parents are siblings married to another pair of siblings.
- •If two brothers marry two sisters, their children are double first cousins.
Double first cousins share about 25% of DNA, similar to half-siblings, not regular first cousins who share 12.5%.
The relationship between ancestors and descendants in a straight line.
- •Your grandmother is in your direct line of ancestry.
Family beyond parents and siblings (grandparents, aunts, uncles, cousins).
- •Your aunt and uncle are part of your extended family.
In many cultures, extended family members live together and share child-rearing duties.
The practice of marrying within one's own tribe or social group.
- •Some communities practice endogamy to preserve cultural traditions.
Many royal families historically practiced endogamy.
The practice of marrying outside one's own tribe or social group.
- •Exogamy helps prevent genetic issues from inbreeding.
Many societies encourage or require exogamy.
Your male parent.
- •Your dad is your father.
Your spouse's father.
- •Your wife's father is your father-in-law.
The child of your aunt or uncle. You share grandparents.
- •Your mom's sister's son is your first cousin.
- •Your father's brother's daughter is your first cousin.
Many people confuse first cousins with second cousins. First cousins share grandparents; second cousins share great-grandparents.
In some cultures, first cousin marriages are common and accepted. In others, they're prohibited or socially discouraged.
Your parent's first cousin, or your first cousin's child.
- •Your dad's first cousin is your first cousin once removed.
- •Your first cousin's son is your first cousin once removed.
"Removed" doesn't mean the relationship was taken away—it means there's a generation gap! "Once removed" = 1 generation apart.
The "removed" terminology is primarily used in English-speaking countries. Many other cultures have specific terms for each generational relationship.
Your grandparent's first cousin, or your first cousin's grandchild.
- •Your grandmother's first cousin is your first cousin twice removed.
- •Your first cousin's granddaughter is your first cousin twice removed.
This is two generations apart from you, not about being "removed" twice from the family!
Someone who shares your great-great-great-grandparents. You are separated by 4 generations from your common ancestors.
- •Your great-great-great-grandmother's other descendants are your fourth cousins.
Someone who shares your great-great-great-great-grandparents.
- •Very distant cousins who share ancestors 6 generations back.
Someone who cares for a child temporarily without legal adoption.
- •Foster parents provide homes for children in need.
A diagram showing family relationships in a tree structure.
- •You can map your ancestors on a family tree.
Relating to brothers or a brotherly relationship.
- •Fraternal twins are siblings born at the same time.
A level in a family tree. Each parent-child step is one generation.
- •You and your siblings are one generation, your parents are the next generation up.
Your child's child.
- •Your son's daughter is your granddaughter (a type of grandchild).
Your child's daughter.
- •Your daughter's daughter is your granddaughter.
Your parent's father.
- •Your mother's father is your grandfather.
Your parent's mother.
- •Your father's mother is your grandmother.
Your parent's parent.
- •Your mom's parents are your grandparents.
Your child's son.
- •Your son's son is your grandson.
Your grandparent's sibling.
- •Your grandmother's sister is your great-aunt.
Sometimes called "grand-aunt" or "grand-uncle" but "great" is more common.
Your grandchild's child.
- •Your grandson's daughter is your great-granddaughter.
Your grandparent's parent.
- •Your grandmother's mother is your great-grandmother.
Your great-grandparent's parent.
- •Your great-grandmother's father is your great-great-grandfather.
Your great-grandchild's child.
- •Your great-granddaughter's son is your great-great-grandson.
Your niece or nephew's child. Same as grand-niece/grand-nephew.
- •Your niece's son is your great-nephew.
Your niece or nephew's child. Also called great-niece/great-nephew.
- •Your nephew's daughter is your grand-niece.
Someone legally responsible for a child who is not the child's parent.
- •If your parents can't care for you, a guardian may be appointed.
A person who sponsors a child at baptism and may help guide their religious upbringing.
- •Your godmother is a special family friend chosen by your parents.
In many Christian traditions, godparents have spiritual responsibilities. In some cultures, they're expected to help raise the child if parents can't.
The study of family history and lineage.
- •Genealogy helps you discover your ancestry.
Someone who shares one parent with you.
- •If you have the same mother but different fathers, you are half-siblings.
Half-siblings are still siblings! The "half" refers to sharing one parent, not to the strength of the relationship.
In blended families, half-siblings often grow up together as full siblings.
A male who shares one parent with you.
- •Your father's son from another relationship is your half-brother.
A female who shares one parent with you.
- •Your mother's daughter from another relationship is your half-sister.
A relative by marriage rather than blood.
- •Your spouse's parents are your in-laws.
Your closest relatives: parents, siblings, spouse, and children.
- •Your parents and siblings are your immediate family.
The state of being related by blood or marriage.
- •Kinship ties connect you to your extended family.
Different cultures define kinship differently. Some cultures have elaborate kinship systems with specific terms for each relationship.
A person in direct line of descent: child, grandchild, great-grandchild.
- •Your daughter's daughter is your lineal descendant.
Direct descent from an ancestor.
- •Your lineage traces back to your great-great-grandparents.
Your female parent.
- •Your mom is your mother.
Your spouse's mother.
- •Your husband's mother is your mother-in-law.
The female head of a family or tribe.
- •Your grandmother might be considered the matriarch of your family.
Related through your mother's side of the family.
- •Your mother's parents are your maternal grandparents.
Tracing descent through the mother's line.
- •In matrilineal societies, inheritance passes through the female line.
Some cultures trace lineage matrilineally, others patrilineally, and some use both systems.
Your sibling's son, or your spouse's sibling's son.
- •Your brother's son is your nephew.
Your sibling's daughter, or your spouse's sibling's daughter.
- •Your sister's daughter is your niece.
A family unit consisting of parents and their children.
- •You, your spouse, and your kids form your nuclear family.
The nuclear family is the basic unit in Western cultures, but many cultures emphasize extended family living arrangements.
A person's child or children.
- •Your children are your offspring.
A child whose parents have died.
- •Children without living parents are orphans.
Your mother or father.
- •Your mom and dad are your parents.
The male head of a family or tribe.
- •Your grandfather might be considered the patriarch of your family.
Related through your father's side of the family.
- •Your father's parents are your paternal grandparents.
Tracing descent through the father's line.
- •In patrilineal societies, surnames and inheritance pass through the male line.
Many Western societies are patrilineal, with children taking their father's surname.
A record of ancestry, especially of purebred animals or distinguished families.
- •Noble families often have documented pedigrees.
The earliest known ancestor of a family line.
- •Your progenitor might be an ancestor from centuries ago.
The number of generations between you and your cousin. "Once removed" means one generation apart.
- •Your parent's first cousin is your first cousin once removed.
- •Your first cousin's child is your first cousin once removed.
- •Your grandparent's first cousin is your first cousin twice removed.
THE BIGGEST MISCONCEPTION: "Removed" doesn't mean someone was disowned or kicked out of the family! It simply means there's a generation gap between you and your cousin.
Most languages don't use "removed" terminology. Instead, they have unique words for each cousin relationship at different generations.
A person connected by blood or marriage.
- •Your aunt is a relative.
The child of your parent's first cousin. You share great-grandparents.
- •Your mom's first cousin's child is your second cousin.
Second cousins are NOT the same as first cousins once removed! Second cousins are in the same generation; first cousins once removed are one generation apart.
Your parent's second cousin, or your second cousin's child.
- •Your father's second cousin is your second cousin once removed.
Your grandparent's second cousin, or your second cousin's grandchild.
- •Your grandmother's second cousin is your second cousin twice removed.
A brother or sister.
- •Your parents' other children are your siblings.
A female sibling who shares one or both parents with you.
- •Your parents' daughter is your sister.
Your sibling's wife, your spouse's sister, or your spouse's sibling's wife.
- •Your brother's wife is your sister-in-law.
Someone who shares your 5×-great-grandparents.
- •Extremely distant cousins who share ancestors 7 generations back.
Your male child.
- •Your male offspring is your son.
Your daughter's husband.
- •Your daughter's husband is your son-in-law.
Relating to sisters or a sisterly relationship.
- •Sororal twins are female siblings born at the same time.
Your husband or wife.
- •The person you married is your spouse.
Your step-parent's son from another relationship.
- •Your stepmother's son is your step-brother.
Step-siblings share no biological parents, unlike half-siblings who share one parent.
Your spouse's child from another relationship.
- •Your wife's daughter from a previous marriage is your step-daughter.
Your parent's husband (not your biological father).
- •Your mother's new husband is your step-father.
Your parent's wife (not your biological mother).
- •Your father's new wife is your step-mother.
Your parent's spouse who is not your biological parent.
- •Your mom's new husband is your step-parent.
The child of your step-parent (no shared biological parents).
- •Your stepfather's daughter from a previous marriage is your step-sister.
Your step-parent's daughter from another relationship.
- •Your stepfather's daughter is your step-sister.
Someone who shares your great-great-grandparents. You are separated by 3 generations from your common ancestors.
- •Your great-great-grandmother's other descendants are your third cousins.
Your parent's third cousin, or your third cousin's child.
- •Your mother's third cousin is your third cousin once removed.
Your parent's brother, or your aunt's husband.
- •Your father's brother is your uncle.
A woman whose spouse has died.
- •After your grandfather died, your grandmother became a widow.
A man whose spouse has died.
- •After your grandmother died, your grandfather became a widower.
The legal process of taking another person's child as your own.
- •Through adoption, non-biological children become legal family members.
Adoption practices and legal frameworks vary widely across cultures. Some cultures have open adoption with ongoing birth parent contact, others have closed adoption.
Your parent through legal adoption (not by birth).
- •Your adoptive parents legally raised you as their child.
A family formed when parents with children from previous relationships marry.
- •When your mom remarried, you became part of a blended family with step-siblings.
Blended families are increasingly common in modern societies.
A group of families claiming descent from a common ancestor.
- •Scottish clans share a common surname and ancestral territory.
Clan structures are important in Scottish, Irish, and many African and Asian cultures.
Two people who share parenting responsibilities for a child, often after separation.
- •After divorce, your parents became co-parents sharing custody.
The family you were born into (your parents and siblings).
- •Your family of origin shapes your early life experiences.
Close friends and loved ones you consider family, regardless of blood ties.
- •Your chosen family includes close friends who feel like siblings.
The concept of chosen family is particularly important in LGBTQ+ communities.
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