Simple past tense and past participle of retrogress.(verb)
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Use "retrogressed" in a sentence
"The Third Preference (professionals and skilled workers) of Employment-Based Petitions (Labor Certification) "retrogressed" (or moved backwards) from March 1, 2003 to unavailable."
"This is a fear of the same trap which Buck constantly sensed in his “dream visions” of the primitive state to which he eventually retrogressed."
"In those politically sensitive areas, however, the Karzai regime not only did not deliver on the 2006 pledges but has even retrogressed on many of the targets."