When I was a kid I was so skinny my nickname at school was “bird legs”. It was humiliating. Kids teased me by saying if I turned sideways I would disappear. I always felt less-than around my meatier classmates.
That’s where I think the crux is. Is the word fat being used to judge and make fun of someone or is it simply describing a person’s body size? If someone called me willowy it might have felt less cruel, but I carried a lot of shame about being skinny and being accused of being anorexic( I was not. ) We should never use our words to shame people.
Kindness always wins the day, no matter what we are saying.
Ironically, I am now about 10 or 15 pounds overweight so I see myself as fat. 🤷‍♀️