1. (noun) butterfly perch, Caesioperca lepidoptera - a fish with a compressed, ovoid body and a continuous dorsal fin without a notch between the spinous and soft portions. Brownish-red to orange-red above, whitish-tan ventrally and a conspiuous dark blotch on each flank near the pectoral fin tips. Numerous  small dark brown spots scattered over the body. Usually found in schools among and above rocky reefs at depths of 5-151 m.