Main Entry: whirl·ing disease

Pronunciation: \ˈhwər(-ə)l-iŋ-, ˈwər(-ə)l-\

Function: noun

: an infectious often fatal disease of salmonid fish (as trout and salmon) that is caused by a protozoan (Myxobolus cerebralis synonym Myxosoma cerebralis) of the order Myxosporidia which attacks cartilage of the head and spinal cord especially of young fish and that causes the fish to swim in circles and is marked by skeletal deformities