part of sensory organ development lateral line development neuromast development GO:0048884 biological_process The process whose specific outcome is the progression of the neuromast over time, from its formation to the mature structure. The neuromast is the sensory organ of the lateral line and is composed of a population of sensory hair cells, and nonsensory supporting cells and mantle cells. Neuromasts are located superficially on the epithelium or in lateral line canals.