In America, we say “tomayto,” “potayto” and “ba-nan-a.” In England, they say “tomahto,” “potahto” and “banahna.”
“In England, they say tomahto, potahto and banahna.”
Nobody says potahto. It’s deliberate gibberish for comic effect from a Gershwin song.
http://www.oxforddictionaries.com/us/definition/english/potato
http://www.oxforddictionaries.com/us/definition/english/tomato
http://www.oxforddictionaries.com/us/definition/english/banana