A "Brain Sister" is a girl who wears glasses and finished high school. However, there is some debate as to whether or not a "Brain Sister" actually wears glasses.
"She was only twentyseventeen, she was a lonely beauty queen, she was a brain sister, Texas Instruments all day..."

Quoted from the Limozeen song "Brain Sister"
by Garboth March 19, 2008
An attractive twenty-something year old who is constantly occupied with a Texas Instruments calculator.
"She was a brain sister - texas instruments all day"
-"Brain Sister" by Limozeen
by Daniel C. Johnston July 31, 2006

Free Daily Email

Type your email address below to get our free Urban Word of the Day every morning!

Emails are sent from daily@urbandictionary.com. We'll never spam you.

×