義妹

1. Origins, structure, and basic meaning

• Structure: 義妹 (ぎまい) combines relational 義 and younger sister 妹 for a younger sister-in-law or stepsister.
• Basic usage: It can refer to a younger female relative by marriage or to a younger sister in a blended family.

2. Common pitfalls and similar expressions

• The exact family link varies
  • 義妹 does not uniquely specify marriage or stepfamily connection; surrounding family information resolves the relationship.