This rare adjective appears only in Proverbs 28:23, describing a person who turns backward or is obstinate. The text presents difficulties, as this is an unusual form and usage. Some scholars suggest emending it or understanding it adverbially as "afterward." The context contrasts someone who rebukes another with one who flatters, suggesting the term describes a negative character trait—perhaps stubbornness, turning away from correction, or regressing rather than progressing in wisdom.