General opposites:
* Romantic: Evokes strong emotions, passion, and idealized love.
* Poetic: Characterized by beauty, imagination, and emotional depth.
* Lyrical: Expressing strong emotions through song-like language.
* Exquisite: Extremely beautiful and delicate.
* Enchanting: Captivating and magical.
* Imaginative: Characterized by creativity and vivid imagery.
* Inspiring: Motivating and uplifting.
More specific opposites:
* Elevated: More sophisticated and elevated in style.
* Evocative: Bringing strong emotions to mind.
* Vivid: Full of life and detail.
* Dramatic: Full of excitement and intensity.
* Intriguing: Arousing curiosity and interest.
* Intense: Full of strong feeling or emotion.
More abstract opposites:
* Extraordinary: Exceptional and unusual.
* Remarkable: Worthy of attention or notice.
* Exceptional: Standing out from the ordinary.
* Unique: One of a kind.
The best opposite for "prosaic" will depend on the specific context in which you're using it.