Understanding Terms: The right name for the right cousin
Conversation on the subject of who is related to whom often bogs down over terminology, particularly when it comes to defining cousins.
Your FIRST COUSIN, of course, is your parent’s brother’s (or sister’s) child. However, the first cousin’s child is not your second cousin as is sometimes thought to be the case, but your first cousin once removed. The child of the first cousin once removed is your first cousin twice removed, and his child your first cousin three times removed.
Your SECOND COUSIN is your grandparents’ brother’s (or sister’s) grand child. That second cousin's child is your second cousin once removed his child your second twice removed and so on.
And your THIRD COUSIN? It’s your great-grandparent’s brother’s (or sister’s) great-grandchild. The third cousin’s child is your third cousin once removed, his child your third cousin twice removed.
Some other occasionally misunderstood terms:
GRANDNEPHEW (or GRANDNIECE) The grandchild of your brother or sister.
GREAT-AUNT (or GREAT-UNCLE) The sister (or brother) of your grandparent.
GREAT-GRANDAUNT (or GREAT-GRANDUNCLE) the sister (or brother) of you great-grandparents.
ANCESTOR The person from who you descend “directly” such as a parent, grandparent or great-grandparent.
DESCENDANT The person who descends “directly” from you, such as a child, grandchild or great Grand-child
LINEAL relationships Those in the “Direct” line of ascent or descent, such as a parent, child, grandparent or grandchild.
COLLATERAL relations - those relatives who are “linked” by a common ancestor, such as aunts, uncles and cousins.