A more thorough explanation:

Definition: To divest (a thing) of its sacred character; to defile or profane (a sacred thing).

• Someone had desecrated the church by spray-painting graffiti on the walls.
• The vandals desecrated the cemetery by knocking over tombstones.
• It is considered disrespectful to desecrate the American flag.

These examples illustrate the definition of desecrate by showing how something that is considered sacred or respected is violated or defiled. In the first example, the church is a place of worship and the graffiti is a disrespectful act that takes away from its sacredness. In the second example, the cemetery is a place where people are laid to rest and the tombstones are a symbol of their memory. Knocking them over is a disrespectful act that takes away from their sacredness. In the third example, the American flag is a symbol of the country and its values. Desecrating it is seen as a disrespectful act that takes away from its sacredness.