Cycloidei

Cy`cloi´de`i


n. pl.1.(Zool.) An order of fishes, formerly proposed by Agassiz, for those with thin, smooth scales, destitute of marginal spines, as the herring and salmon. The group is now regarded as artificial.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.