Word Study
lancelet
CIDE DICTIONARY
lancelet, n. [Lance + -let.].
A small fishlike animal (Amphioxus lanceolatus ), remarkable for the rudimentary condition of its organs. It is the type of the class Leptocardia . See Amphioxus, Leptocardia. [1913 Webster]
OXFORD DICTIONARY
lancelet, n. any small non-vertebrate fishlike chordate of the family Branchiostomidae, that burrows in sand.
Etymology
LANCE n. + -LET, with ref. to its thin form
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