It is legal in most places to marry your second cousin once removed. Whether it is OK to ask that cousin to marry you depends on how you family and community respond to such things.
The son of your second cousin is your second cousin, once removed. You are also his second cousin, once removed.
Your grandmother's second cousin is also your second cousin, but twice removed. The twice removed means the number of generations between you. Your mother's first cousin is your first cousin once removed. If your mother's first cousin has children, they are your second cousins.
Your mother's second cousin twice removed is either your third cousin once removed or your second cousin three times removed. Which it is depends on whether the second cousin twice removed is the grandchild of your mother's second cousin or the grandparent of her fourth cousin.
Your parent's first cousin is your first cousin, once removed. Your parent's first cousin, once removed is your first cousin, twice removed. Your parent's second cousin is your second cousin, once removed. Your parent's second cousin, once removed is your second cousin, twice removed.
Your second cousin's son (or daughter) is your second cousin, once removed.
It means they are one generation removed from you on your family tree. Your second cousin once removed is either your parent's second cousin, or your second cousin's child.
Your parent's first cousin is your first cousin, once removed. Your parent's second cousin is your second cousin, once removed. Your parent's first cousin once removed may be your second cousin.
Your grandfather's first cousin is your first cousin, twice removed. His second cousin is your second cousin, twice removed.
Your mother's first cousin is your first cousin, once removed.Your mother's first cousin, once removed is your second cousin.Your mother's second cousin is your second cousin, once removed.
If your first cousin has a child, you and that child are first cousins, once removed, to each other. If your second cousin has a child, you and that child are second cousins, once removed, to each other.
One of your second cousin's parents is your first cousin once removed.
Your grandfather's first cousin is your first cousin, twice removed. His second cousin is your second cousin, twice removed.