1.
younger brother-in-law, stepbrother (younger)
A younger male relative by marriage or adoption rather than by blood. Can refer to a spouse's younger brother, a younger sister's husband, or a younger stepbrother.
義弟は来年結婚する予定だ。
My brother-in-law is planning to get married next year.
妻の義弟が海外から帰ってきた。
My wife's younger brother came back from abroad.
義弟とは年が近いこともあり、実の兄弟のように仲がいい。
Since my brother-in-law and I are close in age, we get along like real brothers.
USAGE:
A formal term used primarily in writing, official documents, and when precise family relationships need to be specified. In everyday conversation, people more commonly say 妻の弟 (my wife's younger brother) or 旦那の弟 (my husband's younger brother) to be clearer about the exact relationship.
FAMILY TERM PATTERN:
The prefix 義 ('righteous, adopted') marks in-law or step relationships:
- 義兄: older brother-in-law / older stepbrother
- 義姉: older sister-in-law / older stepsister
- 義妹: younger sister-in-law / younger stepsister
- 義父: father-in-law
- 義母: mother-in-law