Charles L'enfant was a French-born American architect who is best known for designing the layout of Washington, D.C. Since he is a historical figure, there aren't many synonyms for his name, but some common variations include Charles Pierre L'enfant, Charles L'Enfant, and Charles L'Enfant Jr. Some may refer to him simply as L'enfant, or even just as the architect of D.C. However, it is important to note that these variations all still refer to the same person and his significant contributions to American architecture and urban planning.