I will second this. I use the two words interchangeably. I would probably use the word fit when talking about liner regression and train when talking about a mo

I will second this. I use the two words interchangeably. I would probably use the word fit when talking about liner regression and train when talking about a more complex ML model that requires more computation. I really don't remember the last time I fitted a regression model by hand, it would have probably been in a college exam.