A girl whose pledging a sorority with you.
Stacey: Whose that? (indicating Myka)
Amber: Oh, Myka? That's my line sister! Love her. We both became apart of Delta Sigma Theta together.
a girl who pledges a sorority with you. she is generally very close to you and has your back.
Person: Who's that in the picture with you?
Me: That's my line sister! We're inseparable! Love her so much!
your sister who stands in LINE with you while pledging,not chilling in a classroom.
whos tha girl you were talking to?
oh thats gia my LINE SISTER, we put in work for our letters
ohhh okk!!!i see you!