When I was about 5 I was in a gym class and the teacher told us all to "sit on our backsides". I and half the class didn't know the word "backside". I think I

When I was about 5 I was in a gym class and the teacher told us all to "sit on our backsides". I and half the class didn't know the word "backside". I think I ended up assuming my "backside" was the side of my back and lying on the floor on my side. Some of my classmates ended up in similar positions, much to the bafflement of the teacher!