the child of your aunt or uncle
"My cousin is my mother's younger brother's son."
The child of a person's uncle or aunt; a first cousin.
"My sister and I are not related, but my daughter is my brother's child, so she is my nephew rather than my own. Wait, that doesn't fit the prompt. Let me try again with the correct meaning: My cousin Sarah came to visit last weekend, as she is the daughter of my aunt."
In plain English: A cousin is your parent's sibling's child, making them someone you share some family history with but are not directly related like brothers or sisters.
"My cousin is visiting from Chicago next week to help me move apartments."
Usage: Use this term to refer specifically to the children of your parents' siblings, distinguishing them from second cousins who share more distant ancestors. Avoid confusing it with "relative," which is a broader category that includes all family members regardless of how closely they are related.
The word "cousin" comes from the Old French term cosin, which originally referred to a collateral male relative who was more distant than a brother. It entered English through Anglo-Norman and Middle French before evolving into its modern meaning for any blood relative of that degree.