The word "progressed" is the past tense of the verb "progress," which means to move forward, develop, or improve in some way.
Antonyms of "progressed" could include "regressed," "declined," and "stagnated."
"Regressed" means to go backward or revert to an earlier, usually less developed or advanced state. When something has progressed, it has made forward strides, but if it regresses, it loses the ground it had gained. For example, a student who was doing well in math and then started making more mistakes and forgetting concepts could be said to have regressed. In contrast to progressing in their understanding and skills, they are moving in the opposite direction.
"Declined" implies a downward movement or a reduction in quality, quantity, or level. If a project had been progressing smoothly but then started to encounter problems and the work slowed down or the results became worse, it could be described as having declined. For instance, a business that was growing steadily (progressing) but then saw a drop in sales and had to lay off employees is experiencing a decline.
"Stagnated" means to stop developing or moving forward and remain at a standstill. While progress indicates movement and improvement, stagnation is the lack of such movement. For example, a small town that once had new businesses opening and infrastructure improvements (progressing) but then saw no new development for years and everything stayed the same could be said to have stagnated.
In summary, while "progressed" shows forward movement and development, its antonyms like "regressed," "declined," and "stagnated" represent the opposite situations of going backward, going downward, or remaining motionless in terms of growth and improvement.