The constellation or astrological sign of Pisces; often referred to as 双鱼座 shuāng​yú​zuò

(literary) A letter or correspondence; derived from the ancient custom of enclosing letters between two wooden boards carved in the shape of a fish

(historical) A traditional Chinese auspicious motif featuring two fish, often representing good luck, wealth, or harmony; common in ancient bronze basins and artwork

Two fish; a pair of fish