In Mishpatim (and perhaps elsewhere), the Tora refers to an animal incurring or causing damage, and calls it a shor, שור, commonly translated ox.
In Pin'chas (and Achare and perhaps elsewhere), the Tora refers to an animal being brought as a sacrifical offering, and calls it a par, פר, commonly translated bull.
In English, ox refers to a castrated adult male that's used for pulling something, and bull refers to an adult male that hasn't been castrated. Is that, in fact, the difference between a שור and a פר: that a שור has been castrated and a פר has not? Or what is the difference between a שור and a פר? And why is the word שור used when discussing damage and the word פר used when discussing offerings?