Family relationship names

The words for every kind of relative, from grandparent to cousin-in-law, with the one-line definition you can read out at the table.

By blood

Parent
Your mother or father. 1 generation up.
Grandparent
Your parent's parent. Each "great-" adds a generation: great-grandparent, great-great-grandparent, then 3rd great-grandparent.
Sibling
Brother or sister: you share both parents.
Half-sibling
You share exactly one parent.
Aunt / uncle
Your parent's sibling. Gender-neutral: pibling.
Great-aunt / great-uncle
Your grandparent's sibling. Genealogists may say grand-aunt or grand-uncle.
Niece / nephew
Your sibling's child. Gender-neutral: nibling.
Great-niece / great-nephew
Your sibling's grandchild; also called grandniece or grandnephew.
First cousin
Child of your aunt or uncle. You share grandparents.
Second cousin
Child of your parent's first cousin. You share great-grandparents.
Third cousin
You share great-great-grandparents.
Once removed
One generation apart on a cousin line; twice removed is two generations apart.
Half-cousin
Cousins who share one grandparent rather than a couple.
Double cousin
Cousins related through both parents, e.g. two sisters married two brothers.

By marriage & informal

Spouse
Husband, wife or partner by marriage.
Parent-in-law
Your spouse's mother or father.
Sibling-in-law
Your spouse's sibling, or your sibling's spouse. Also your spouse's sibling's spouse in everyday use.
Child-in-law
Your child's spouse: son-in-law or daughter-in-law.
Co-parents-in-law
The parents of your child's spouse. Yiddish has a single word, machatunim; Spanish has consuegros.
Cousin-in-law
Your spouse's cousin or your cousin's spouse.
Step-parent
Your parent's spouse who is not your biological parent.
Step-sibling
Your step-parent's child. No shared parents.
Step-cousin
Your step-parent's niece or nephew. No blood link.
Nibling
Gender-neutral word for a niece or nephew, coined by linguist Samuel Martin in 1951.
Pibling
Gender-neutral word for an aunt or uncle (parent's sibling).
Kissing cousin
Informal: a relative familiar enough to kiss hello, often a distant cousin.
Courtesy aunt / uncle
A close family friend, or a parent's cousin, called aunt or uncle out of affection.

Words English doesn't have

Many languages name relatives more precisely than English. Mandarin distinguishes older from younger siblings and maternal from paternal grandparents; Swedish says morbror (mother's brother) and farbror (father's brother) instead of one word for uncle. English leans on "cousin" for a huge range of people, which is exactly why terms like "second cousin once removed" exist, and why a relationship calculator helps.

Questions people ask

What do you call your sibling's children without saying niece or nephew?

Nibling is the gender-neutral term. The matching word for an aunt or uncle is pibling.

What do you call your child's in-laws?

English has no single word; people say co-parents-in-law or "my son's in-laws". Yiddish uses machatunim and Spanish consuegros.

Is a step-relative the same as a half-relative?

No. Half-relatives share one parent or ancestor by blood. Step-relatives are connected only through a marriage.