apathetic
The definition for apathetic is "Showing little or no emotion." Used in a sentence: Carmine was concerned about his usually cheerful brother's apathetic attitude.
derivative
The definition for derivative is "Lacking originality." Used in a sentence: Critics panned the movie as a derivative version of last year's Best Picture.
melodious
The definition for melodious is "Having a pleasing melody." Used in a sentence: The melodious sounds of the symphony soothed Tim after his trying day.
regale
The definition for regale is "To amuse." Used in a sentence: My clever brother Jeffrey regaled the dinner guests with tales of his adventures.
retroactive
The definition for retroactive is "effective as of a prior time or condition." Used in a sentence: The retroactive law made even past infractions punishable.