Jumper Dress (that doesn't jump)

I decided to make J. a jumper (in her favourite colour!) but when I told her what I was doing, I didn't even think about the fact that she wouldn't know what a jumper was!  When I got her to try it on, she ran to the mirror, bounced around and then looked at me with sad eyes.  She said "It doesn't jump".  I knew what she meant but I laughed and then when A. got home, I told him about it.  J. got extremely offended, and said, complete with the requisite "you're so dumb" roll of her eyes, "I didn't think it would jump, Mom, but it's supposed to twirl".  Despite the lack of twirl, she tried (unsuccessfully) to wear it to bed and was very excited to be able to wear it to school today.