Tah

A word used towards people who are rejects of a family or a close circle of people.

A brother gets upset with his sibling who is younger than him and seems to be the least favorite in the family. The older brother would then call his younger brother a "tah" meaning reject or outcast.

So in this context "tah" menas: A word used towards people who are rejects of a family or a close circle of people.