retrogress

/ˌrɛtrəˈɡrɛs/
verb
  1. To return to an earlier, worse, or less developed state.
    • If we don't maintain the software, it will retrogress to an unstable version.
    • The country's economy started to retrogress after the political crisis.
    • Without practice, his language skills began to retrogress.
Antonyms
What does "retrogress" mean? | whatsthatwordmean | whatsthatwordmean