Here is a definition provided by Wikipedia:
A croquembouche or croquenbouche is a French dessert, a kind of pièce montée often served at weddings, baptisms, and first communions. It is a high cone of profiteroles (choux filled with pastry cream) bound with caramel, and usually decorated with threads of caramel, sugared almonds, chocolate, flowers, or ribbons.
The name comes from the French words 'Croque en bouche' meaning 'crunch in the mouth'.
The choux buns can also be made with savoury fillings.
Alternative spellings include croquenbouche and croquebouche.