ubiquitous language concept
Within a bounded context, everyone — engineers, product, domain experts — uses the same words to mean the same things, and the code reflects those words exactly.
Within a bounded context, everyone — engineers, product, domain experts — uses the same words to mean the same things, and the code reflects those words exactly. No translation layer between business and code. When the language drifts, you have a model bug, not a translation bug. The language *is* the model.