Big boned

1.An excuse used by fat people when they don't want to admit that they are fat.
2. A nice way of saying one is fat, built in an odd way, or a giant.

3. When someone's bones are larger than average (this can also be described as "stocky"). Can also be used to say someone is fat in a polite way.

In portuguese the expression is generally translated as "ossos largos" ou "pessoa de ossos largos", but it is unusual between native speakers.

Fonte: Urban Dictionary