This is the 5804th most frequent Russian word.
пышным
Lush, splendid, or luxuriant.
Here, 'пышным' is used as an adjective in its instrumental case form, describing the lavish or grand quality of the dress.
Её пышным платьем любовались все гости.
Everyone admired her magnificent dress.
In this sentence, 'пышные' is the nominative plural form of the adjective, describing the luxurious and full appearances of the foliage.
Осенью деревья одеваются в пышные наряды.
In autumn, the trees dress in luxuriant attire.
Here, 'пышных' is in the genitive plural case, indicating an abundance of adorned or excessive qualities associated with the words and expressions.