En croix, meaning in the shape of a cross, has become the modern foundation of barre work patterning, but it actually rests on the vestiges of an ancient cultural foundation. La croix means the cross, a timeless symbol, but can one be en croix? Does the origin of this term go beyond the basic symbol of a cross?
En croix is pronounced [ɑ̃ kʀwa]. En- sounds almost like "on" in English except that the n isn't pronounced and the vowel sound comes through both the nose and the mouth. -croix- sounds like the combination of k + w followed by an open "ah" sound.
Any type of battement can be performed en croix meaning that the action of the working leg traces the outline of a cross, moving devant, à la seconde, derrière or derrière, à la seconde, devant.
The movement is simple so let's get back to those ancient foundations. By laying a cross flat, you can imagine the action of following the lines of the cross with the working leg, but as a dancer and as a teacher, this always seemed contrived to me. It wasn't until much later that I realized how en croix could be interpreted in a different, more physical way. La croix also means the point where the nave and the transept of the church or cathedral meet. If one were standing en croix, one would be standing in the middle of a giant cross intentionally laid flat through architectural design.
Whether the original intention was a simple cross or the architectural intersection of the church, the cross and cathedral were familiar to all classes in France from the time of the first cathedrals (long before the codification of ballet), which were built by the faithful who believed their back breaking work on these structures brought them closer to God. It's unclear during which time period en croix was brought into ballet vocabulary, it is likely that it was used long before it was ever officially defined or included in the dictionaries of dance that were created. It was an idea and a shape so common that definition likely remained unnecessary for a great number of years.