Sister (noun)

1. A female sibling; a daughter of the same parents as another person.
2. A female member of a religious community, especially a nun.
3. A female friend or companion who shares one's interests and experiences.
4. A member of a women's organization, especially a sorority or women's club.

Origin:

From middle english sister, suster, from old english sweostor, sweoster ("sister"), from proto-germanic *swestēr ("sister"), from proto-indo-european *swésōr.

Examples:

1. She has an older sister who is a doctor.
2. The sisters at the convent sang hymns every morning.
3. She and her sister bonded over their shared love of music.
4. My sister is a member of the local women's club.
5. She is close with her sister and they often travel together.