Zed is the last letter in the alphabet. It appears that this is something Americans changed when we changed the language to create a new identity. Zed comes from the French zede which comes from the Greek zeta. We changed it to fall in line with how we say the letters b, d, v and so on.

I don't see myself ever saying this but when I have children and am singing the alphabet, I will need to remember its zed :)

All the Best!

American to Britain