look up any word:
1. Soul Sister
Soul: the immaterial part of a person; the actuating cause of an individual life

Sister: a female person who has the same parents as another person

Soul Sister: Someone who fully understands you. Like a soulmate, but not someone you want to marry and make babies with. The sister of your soul.
1)As quoted in Confessions of a Teenage Drama Queen, "Ella Gerard you are the sister of my soul"

2)Hayley just gets me, she understand everything about me, she's my soul sister.
Soul Sister videos
2. Soul Sister
The female equivalent of a blood brother. A best friend of the female persuasion that you consider family. Most times, the feeling is mutual.
Jackie and Rachel are soul sisters. It's like they have the same mother!
3. soul sister
A referent for a Black female. Since at least the early 2000s "soul sister" is usually shortened to sista without the word "soul". "Soul brother" brotha is the equivalent referent for a Black male.
1.Soul sister #9, sock it to me one more tme.

2. That soul sister knows she's lookin good.
rss and gcal