Definition of 義妹 (ぎまい)
ぎまい
                        義妹
ぎまい
gimai
Common word
noun
1.
sister-in-law (spouse's younger sister or younger brother's wife)
2.
younger stepsister, younger adopted sister, non-blood-related younger sister
Other readings:
                義妹【いもうと】[1]
                Notes:
                - word containing irregular kana usage
Related Kanji
| 義 | righteousness, justice, morality, honor, loyalty, meaning | 
| 妹 | younger sister |