'Dīng yōu' is a formal classical Chinese term referring to the Confucian mourning obligation observed by officials upon the death of their father. The character '丁' (dīng) here functions as a verb meaning 'to encounter' or 'to be struck by'—in this context, 'to be confronted with' a major familial event; '忧' (yōu) means 'grief', 'sorrow', or 'mourning'. Together, they signify the solemn duty of withdrawing from official service for 27 months to mourn and honor one’s deceased father—a practice deeply rooted in filial piety and hierarchical family ethics.

Historically, 'dīng yōu' was mandatory for civil servants during imperial China; failure to observe it could lead to dismissal or censure. Though no longer legally enforced, the term remains in historical texts, scholarly discussions of Confucian ritual, and occasionally in modern literary or ceremonial contexts to evoke traditional values. It specifically denotes paternal mourning—not maternal—and distinguishes itself from general grief terms by its institutional, ritualized nature.