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Webster 1913 Edition
Cycloidei
‖
Cy-cloi′de-i
(s?-kloi′d?-?)
, Noun.
 pl.
 [NL., fr. Gr. 
κύκλοσ 
circle + -oid
.] (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.