血縁

1. Origins, structure, and basic meaning

• Structure: 血縁 is read as けつえん and is a noun for a biological family connection or blood relation.
• Basic usage: Its absence appears in 血縁がない, while organizing a group around it appears in 血縁を中心にする.

2. Common pitfalls and similar expressions

• Relationship and emotional closeness
  • People can grow up like siblings without a blood relation, so closeness and biological connection are distinct.
• Difference from 親族
  • 親族 identifies people counted as relatives, while 血縁 centers on the blood connection itself.