(n) a lie designed to injure a reputation; the practice of making lying, hurtful statements

She was spreading calumnies about her opponent. 

(v) to deny, dispute, or contradict

(n) gainsayer: a person who denies or contradicts

(n) a long, passionate, and forceful speech, especially one delivered in public

(v) to address or speak to (someone) in a harangue

He harangued the crown into a frenzy.

(v) to cast doubt on

The lawyer impugned the witness's story. He didn't believe it based on contradictory evidence. 

(v) to protest strongly, complain bitterly; to rail against

The clergy inveighed against immorality. 

(v) to beat or whip severely; to scold or reprimand harshly; berate

She lambasted me for being late.

(v) to berate sharply

(n) blame, verbal abuse, disgrace; discredit

ob- : against

loqui : speak

(n) a wooden framework built on a post, with holes for securing the head and hands, formerly used to expose an offender to public humiliation and insults as punishment

(v) to expose to public insults or abuse

The press pilloried him for his foolish remark.

(v) to use or address with harsh or abusive language; revile

(n) vituperator

(n) the sound made by a bell rung slowly, especially for a death or funeral

The death knell of Western Communism was the collapse of the Berlin Wall. 

(v) to refuse or deny (rights, comforts, etc.) to oneself, renounce; give up

Priests abnegate bodily pleasures when they join the priesthood.

(adj) leaving no opportunity or chance for denial or refusal; acting like a dictator in expecting others to be obeyed

The peremptory boss was difficult to work with because he was so dictatorial.

(adj) hard to understand

Many scientists have put forth abstruse theories of time and space.

(adj) relating to or dealing with very deep, difficult, obscure, or abstract subject matter; 

beyond ordinary knowledge or understanding; esoteric; obscure; little known

The recondite treatise was difficult to understand because the theology was very abstract. 

The recondite fact surprised many people. 

(adj) not clear because of having been stirred up; clouded; muddy; disturbed

The river water after the rainstorm was turbid; we couldn't see through the water. 

(adj) having an offensive odor

The fetid corpse was unbearable; it was too stinky to be around. 

(adj) creating ill will; causing resentment or envy; offensive or unfairly pointing out similarities or differences

The supervisor had the invidious job of evaluating teachers. 

The invidious comparison between the two sisters was hurtful. 

(adj) allowing light to pass most easily, as glass; translucent; clear in meaning or expression 

The pellucid waters allowed you to see to the bottom of the stream. 

The author had a pellucid way of writing that enabled his readers to easily understand what he was saying. 

(n) a feeling of uneasiness for doing wrong; remorse

The victim felt no compunction in shooting the teens who had attacked him. 

The student had no compunctions about cheating. 

(v) to atone for; to make amends or reparation for

On Yom Kippur (the day of atonement), Jews expiate their sins committed throughout the year. 

(adj) equivalent, as in value, force, effect, or signification

That insult was tantamount to a slap in the face. 

His angry speech was tantamount to a declaration of war. 

(adj) serving as a substitute; synthetic; artificial

Chicory is an ersatz coffee made from a type of flower. 

(n) deliberate treachery or betrayal of another; a deliberate breach of faith or trust

Perfidy should not go unpunished. 

(adj) not genuine; counterfeit; (of arguments): poorly reasoned, faulty in reasoning (e.g. logical fallacies)

The argument was spurious; there were many faults in his reasoning. 

(v) to clear from a charge of guilt or fault; free from blame; vindicate

The judge exculpated the accused and set him free.

(v) to soothe, to relieve (pain, etc.) without curing; alleviate pain; 

to try to make (a wrong act or an offense) seem less serious by giving excuses, etc. 

The man palliated his crime by claiming it was necessary in order to feed his family.