- making a hypocritical show of religious devotion, piety, righteousness, etc.: They resented his sanctimonious comments on immorality in America.
- Obsolete. holy; sacred.
- affecting piety or making a display of holiness
adj.c.1600 (in “Measure for Measure,” with the disparaging sense “making a show of sanctity, affecting an appearance of holiness”), from sanctimony + -ous. The un-ironic, literal sense was used occasionally in English from c.1600 to c.1800. Related: Sanctimoniously; sanctimoniousness.