Answer: festooned

AnswerCrossword Clue
FESTOONEDBedecked.
FESTOONEDDecorated, in a way.
FESTOONEDLike some party rooms
FESTOONEDDecked out
festoonedAdorn (a place) with chains, garlands, or other decorations
festoonedFESTOON, to adorn with garlands