(Latin: from, away from, off; down; wholly, entirely, utterly, complete; reverse the action of, undo; the negation or reversal of the notion expressed in the primary or root word)

decivilize (verb), decivilizes; decivilized; decivilizing
To move from a developed society and an advanced culture to one that is of a wild or savage behavior: After centuries, the Romans were decivilized by the invading barbarians. Similar developments can also be applicable to the Egyptians and other ancient cultures.
declaim (verb), declaims; declaimed; declaiming
1. To speak aloud with studied rhetorical force and expression on a specific theme, as an exercise in public oratory: The preacher stood on the street corner, declaiming his beliefs about the evils of excessive drinking of liquor and smoking.
2. To speak in a passionate manner, appealing to emotions rather than to reason: The students stood in front of the university committee to declaim their membership in the "Flat Earth Society".

The senator declaimed against passing a bill that would raise taxes.

The priest was declaiming the funeral oration in loud and emotional feelings.

declaimer (s) (noun), declaimers (pl)
An individual who speaks with passionate expression, typically attempting to sway a crowd's mood or behavior: Mr. Tully performed as a declaimer at recruitment rallies, hoping to persuade young people to join his political objectives.

Almost any opinion can sound convincing if a declaimer speaks loudly and with conviction.

declamation (s) (noun), declamations (pl)
A public speech the purpose of which is to arouse passions, to harangue, or to excite the listener's agreement to take action: The local newspaper reported on the declamations of the speaker who had radical and persuasive viewpoints on the subject of climate change.
declamatory (adjective), more declamatory, most declamatory
Descriptive of a rhetorical style of speaking, characterized by forcefully putting forth an opinion or point of view in a way that is loud and forceful: As a university student during the 1960's, Maureen remembers hearing some very declamatory speeches about civil rights and liberties from pro and negative viewpoints that were often loud and emotional.
Serving, or tending, to declare or to state.
declare (verb), declares; declared; declaring
declass (verb), declasses; declassed; declassing