"Prosaic" means having the style or diction of prose; lacking poetic beauty. More commonly, it means dull, unimaginative, or ordinary. The word suggests something commonplace and uninspired. The correct antonym is "Extraordinary," which means very unusual or remarkable; greatly surpassing the common.

"Mellifluous" means (of a voice or words) sweet or musical; pleasant to hear. It describes a smooth, flowing, and harmonious sound. The correct antonym is "Cacophonous," which means involving or producing a harsh, discordant mixture of sounds; jarring or unpleasant.

"Perfunctory" means (of an action or gesture) carried out with a minimum of effort or reflection; done carelessly or merely as a duty. It suggests a lack of genuine interest or depth. The correct antonym is "Thorough," which means performed or executed with great attention to detail; complete and painstaking.

"Chicanery" is a noun that means the use of trickery or deception to achieve a political, financial, or legal purpose; deceit or dishonesty. The most direct antonym is "Candor," which means the quality of being open and honest in expression; frankness.

"Ephemeral" means lasting for a very short time; short-lived. It describes something fleeting or momentary. The correct antonym is "Lasting," which means enduring or remaining for a long period of time; durable.

"Pervasive" means spreading widely throughout an area or a group of people; widespread or omnipresent. It describes something that is present everywhere. The correct antonym is "Rare," which means not occurring very often; uncommon or infrequent in occurrence or distribution.

"Tenuous" means very weak or slight; lacking a firm basis, stability, or substance. It suggests something thin, fragile, or flimsy. The correct antonym is "Substantial," which means of considerable importance, size, or worth; solid and well-founded.

"Clemency" is a noun meaning mercy, leniency, or mildness, especially toward an offender or enemy. It often refers to the power of an executive figure (like a president or governor) to reduce a sentence. The correct antonym is "Severity," which means the quality or state of being strict or harsh; it implies sternness and lack of mercy.

"Fervent" means having or displaying a passionate intensity or enthusiasm. The word suggests a deep, burning feeling or dedication. The correct antonym is "Indifferent," which means having no particular interest or sympathy; unconcerned or apathetic.

"Gregarious" means fond of company; sociable or outgoing. It refers to a person who enjoys being around others and is social. The correct antonym is "Retiring," which means reserved, shy, or withdrawn from society, preferring solitude or quiet company.