The point at which one's overall number of friends on Facebook (or other social networking site) Stays at roughly the same number. This phenomenon occurs when one has maintained a profile for a few years, and the rate at which that person is making new friends is equal to the rate at which old friends forget about the person and remove him/her from their friends lists.
Person 1: "That's so weird... I just added Mike and Jane as friends last week, but I'm back to 563 friends again."

Person 2: "Ah, I see you have finally reached friend equilibrium."
by Teeeeeeeej July 14, 2010
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