Definition of echiuroid
: any of a phylum (Echiura syn. Echiuroidea) of marine worms of uncertain taxonomic affinities that have a sensitive but nonretractile proboscis above the mouth
Origin and Etymology of echiuroid
New Latin Echiuroidea or Echiura, ultimately from Greek echis viper + oura tail
First Known Use: circa 1889
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