The F Word

My 6 year old daughter was recounting her day at school today.  She mentioned a few people and described them by their shapes - one woman in particular was the "F" word.  I asked her what that meant and here's the conversation that followed:

Me:  So, what is the "F" word?
DD:  You know - "fat" but I didn't want to hurt her feelings by telling her that.
Me:  Well, people are all sorts of shapes you know.
DD:  Yeah, some people are round like circles, some are like rectangles...
Me:  Yes, that's right.
DD:  And you, you're sort of a half circle.

I guess that's one way to put it.