No, no, no- a meatball and popcorn chicken are not the same thing.
A meatball is ground beef and seasoning rolled into a sphere and baked or pan-fried.
Popcorn chicken is chicken chunks, battered and deep fried.
Now, if you took ground chicken and seasoned it, rolled it into balls, and baked it, you'd have chicken meatballs. Why we specify chicken but not beef when it's all meat anyway is cultural- traditionally meatballs are beef, so it doesn't need to be stated.
If you took chunks of beef, battered and deep fried it, you'd have popcorn beef. We specify the meat regardless here to distinguish from actual popcorn. Incidentally, popcorn pork is delicious. My fiancé makes it sometimes.
This is all just semantics, though- the golden cow isn't going to care about how we identify dishes made from its brethren's carcasses when it returns to destroy our civilization and all we love.