We all have families—even aliens do—but sometimes we don’t know which word to use for particular members, especially those who are not part of our immediate family.
Just to be sure, these are the words in family vocabulary you might wish to know:
Nuclear family: consists of father, mother and their child/children.
Extended family: the nuclear family and families of both parents all together.
Monogamy: the practice of being married to one person at a time.
Polygamy: the practice of being married to more than one person at the same time.
Bigamy: the crime of marrying another person while still married to one.
Blood relation: related by blood rather than through marriage.
Relatives: people connected by blood or marriage.
Spouse: your husband or your wife.
Paternal: of your father (e.g. paternal grandfather).
Maternal: of your mother (e.g. maternal grandparents).
Great-grandfather: the father of your grandfather or grandmother.
Great-grandmother: the mother of your grandfather or grandmother.
*Both are called great-grandparents.
Grandfather: the father of your father or mother.
Grandmother: the mother of your father or mother.
*Both are called grandparents.
Grandson: the son of your son or daughter.
Granddaughter: the daughter of your son or daughter.
*Both are called grandchildren.
Father: your male parent.
Mother: your female parent.
*Both are called parents.
Brother: the male child of your parents.
Sister: the female child of your parents.
*Both are called siblings.
Son: your male child.
Daughter: your female child.
*Both are called children.
stepfather: the husband of your mother who is not your biological father.
stepmother: the wife of your father who is not your biological mother.
*Each of them is a step-parent(UK); step parent(UK); stepparent(US).
stepbrother: the son of your stepfather or stepmother.
stepsister: the daughter of your stepfather or stepmother.
*Both are step-siblings (UK); step siblings (UK); stepsiblings (US).
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