noun

a person who is guided more by ideals than by practical considerations.

they were idealists and visionaries, in love with the work they had undertaken

utopian,visionary,wishful thinker,pipe-dreamer,fantasist,fantasizer,romantic,romanticist,romancer,castle-builder,Walter Mitty,Don Quixote,dreamer,daydreamer,impractical person,unrealistic person,fantast,reverist