Retrogressed is a word that refers to a decline or a setback in progress or development. There are several synonyms that can be used in place of retrogressed, such as regressed, degenerated, deteriorated, declined, worsened, deteriorated, deteriorated or lapsed. All these synonyms express the idea of something having devolved or gone backward from a previous, more advanced state. Regressed implies a return to a former state, while degenerated suggests a loss of quality or value. Deteriorated and declined suggest a gradual and continuous decline, while worsened carries an idea of a sudden and greater negative change. Knowing synonyms for retrogressed is helpful in developing a more nuanced and varied vocabulary.