It seems that head cheese is an American idiom:
In England, head cheese is referred to as brawn, in Scotland as "Potted Head", and in France as fromage de tête, which translates as "cheese of the head". In Louisiana, the highly seasoned "Hog's Head Cheese" is very popular as a cold cut or appetizer. It is also something of a staple of soul food, and may also be known as "souse meat" or simply "souse".So the headcheese subtitle on the Polish cold cut in my grocers is a Yank term that got into the vernacular as a literal translation - from Louisiana's Cajuns I suppose - of the French term.
Hmmmmm, everything is deeply intertwingled, though I'd certainly have a petite morte in delight and surprise if there was a straightforward French term for anything.