Intransigent is a formal word that describes a person who refuses to compromise or abandon an often extreme position or attitude. It can also describe a thing, such as a system or point of view, that shows the same kind of stubbornness.

// Despite the mediator's best efforts, the opposing sides in the dispute remained intransigent.

Zest refers to an enjoyably exciting quality, or to keen enjoyment itself. In culinary use, zest refers to small pieces of the peel of a lemon, lime, orange, or other citrus fruit used as flavoring.

// His humor added zest to the presentation's admittedly dry material.

// The couple has a zest for travel and adventure.

// Lime zest adds a burst of brightness to the dessert's rich flavor.

Fugacious is a formal word that describes something that lasts only a short time.

// The rock band’s early success proved fugacious; within two years its members had moved on to other careers.

// Savor the enduring pleasures of life as intensely as the fugacious ones.

A rendition, simply put, is the act or result of rendering something. That thing may be a performance or interpretation, a depiction, or a translation. In US law, rendition refers to the surrender by a state of a fugitive to another state that is charging the fugitive with a crime.

// Their signature meatloaf is a fine rendition of a classic recipe.

// Theatergoers have been eager for an English rendition of the acclaimed French play.

Taciturn is a formal word that describes someone who tends to be quiet or who tends to speak infrequently.

// One of the twins was taciturn and shy, while the other one was more outgoing.

Numinous is a formal, often literary, word that typically describes things that have a mysterious or spiritual quality. It can also describe something holy or something that appeals to one's aesthetic sense.

// We were overcome by the numinous atmosphere of the catacombs.

// The artist's sculptures dominate the space, their numinous presence welcoming museum-goers to a foreign world.

To coruscate is to give off or reflect light in bright beams or flashes. Coruscate is used as a synonym of sparkle and may also be used to mean "to be brilliant or showy in technique or style."

// She placed a bid on a classic car from the 1950s, replete with yards of coruscating chrome.

Exorbitant describes something that goes far beyond what is fair, reasonable, or expected (as by being too high, too expensive, etc.).

// The cost of our stay was so exorbitant you would have thought that we had bought the hotel and not just spent a few nights there.