big sister

American  

noun

1. an elder sister.

2. (sometimes initial capital letters) a woman who individually or as a member of an organized group undertakes to sponsor or assist a girl in need of help or guidance.

3. (sometimes initial capital letters) a young woman in the junior or senior class in college who advises a young woman in the freshman class on studies, social activities, etc., often as a part of a sorority program.

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Example Sentences

And although the phrase was thrown at Ariana Grande before a screening of “Wicked,” her work as Glinda was big sister at best.

From Salon • May 10, 2026

"You were a constant, a guiding force, and to me, someone I admired and learned from - like a big sister, a woman of immense heart, wisdom, and generosity."

From BBC • Mar. 25, 2026

What she found was that the relationship went beyond business; she sees her agent as part negotiator, part therapist, part big sister.

From The Wall Street Journal • Mar. 4, 2026

She paid tribute to Sakamoto who is affectionately called "big sister" by her teammates.

From Barron's • Feb. 20, 2026

Kristen Jarvis had been replaced by Chynna Clayton, a hardworking young woman from Miami who quickly became another big sister to our girls and was central to keeping my life running smoothly.

From "Becoming" by Michelle Obama