big brother

noun3

1. •
   A sibling's older brother.

   • If you don't give me back my toys I'll tell my big brother!
2. •
   (figurative) Something that is bigger in comparison.
3. •
   (figurative) early mobile phones (in China)

   • Due to the size of Big Brother and the fact that people who used it were mostly big brothers in the business world, this thing quickly became a status symbol. — 2018

noun2

1. •
   Unwarranted, invasive, and discreet surveillance, especially of a people by its government.

   • Some people are worried about marketing calls at dinnertime or junk mail or spam, while others are more concerned about Big Brother. — 2002
2. •
   Any omnipresent authority or figurehead representing oppressive control.