A common practice used to continuously eliminate unwanted social media connections. When a complete stranger or frenemy celebrates a birthday, the user opts to remove that individual as a friend. The rationale is relatively simple: if a person does not care enough to offer well-wishes on another person's birthday, the two probably should not be friends anyway.

It is important to note that the Birthday Axe is not to be used by the ACTUAL birthday celebrant. If someone failed to acknowledge your birthday, you need to get over it, Little Pussy Bitch.
Person A: Dude, didn't you used to have like a million Facebook friends?

Person B: Yeah, but I birthday axed like 70 random people in October alone. It felt good doing it, too.
by The State of Affairs October 27, 2011
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