Girl's pinafore (apron?) - Suzy Ultman's laminated Little Kukla

I've finished my first girl's pinafore using Suzy Ultman's laminated (or slicker) fabric called Little Kukla and I'm surprised how well it turned out. It's the right size for a 3 to 5 year old and very useful for messy cooks or growing artists! Just wipe over to clean!

Can somebody please explain to me the difference between pinafore and apron. I grew up in the UK and my Grandma and Mum taught me that a pinafore is the garment with the bit that covers your chest too. An apron is the garment that just covers you from the waist down. Now I searched for photos of aprons in Google and a load of pinafores appeared. Did I misunderstand this difference? Can anybody explain this to me?

This fabric is really jolly and fun too. As I wrote in a previous post, I love Suzy Ultman's fabric and in particular Little Kukla. I have this fabric in laminated and not.

Now I'm working on some key rings made from the same material to sell to raise money at Ella's school "End of Year Concert". They're looking good too, it must be the fabric that makes everything look good! I'll have some photos soon...