下界

下界	xià jiè	lower bound (math.) / world of mortals / (of gods) to descend to the world of mortals
下	xià	down / downwards / below / lower / later / next (week etc) / second (of two parts) / to decline / to go down / to arrive at (a decision, conclusion etc) / measure word to show the frequency of an action
界	jiè	(bound form) boundary; border / (bound form) realm