Most workaday refers to something that is ordinary, plain and unremarkable. Its antonyms would be words that describe something that is unusual, special and remarkable. These antonyms include:
1. Extravagant
2. Exceptional
3. Deluxe
4. Opulent
5. Exclusive
6. Splendid
7. Luxurious
8. Unique
9. Premium
10. Elite
These words are used to describe objects, experiences or events that are out of the ordinary, a break from the mundaneness of daily life. They are often associated with luxury and expense, and evoke a sense of exclusivity and elegance. When looking for ways to describe something that is not just workaday but exceptional, these antonyms offer a wellspring of options.