A girl from your youth who was cute. You don't see her for years, but when she resurfaces, she is really fat. Alternately, the term can also be used for a cute girl from your past who gets really fat, but then loses the weight.
The etymology of this term stems from its use as a character name on the popular
sitcom "
Boy Meets World". The aforementioned Tapanga was played by actress Danielle
Fishel who gained a large amount of weight after the show ended.
Wow, I haven't seen
Natalie since
high school, but she really went full Tapanga on us.