The verb deplore is used to express strong disapproval of something. If you really, really hate the way your mom makes meatloaf, then it's safe to say you deplore it.
Deplore comes from Latin roots that mean "to bewail or lament." So if you deplore something, you object to it because it brings you sorrow or grief. People often deplore things that they regret or feel bad about. You might deplore the inhumane treatment of animals or the deforestation of the Amazon. Or maybe you just deplore your wardrobe choices from middle school.