Sanctimony
Etymology
From Latin sanctimonia, "sacredness, holiness," from sanctus, "holy, consecrated" (from sancire, "to make sacred"). Strikingly, the word once meant genuine holiness. Over time it curdled: what had named real sanctity came to name its counterfeit — the affected, self-satisfied piety that only performs goodness.
noun · /SANK-tih-moh-nee/
A show of moral or religious superiority — righteousness worn as a display rather than genuinely felt.
What it names
The vice of the person who parades their own virtue, lecturing others from a height of goodness they have mostly manufactured.
Example
There was a note of sanctimony in his email about office recycling that made everyone want to litter.
Related idea
Piety is sincere devotion and reverence; sanctimony is its hollow imitation — the same posture struck for the sake of looking, and feeling, superior.