acorn worm
or a·corn·worm
noun
any of several burrowing, often brilliantly colored hemichordates of the class Enteropneusta, usually found in intertidal sand and mud, having an acorn-shaped proboscis and collar.
Origin of acorn worm
First recorded in 1885–90
Words nearby acorn worm
acorn spoon,
acorn squash,
acorn sugar,
acorn tube,
acorn valve,
acorn worm,
acosta's disease,
acotyledon,
acouasm,
acouchi,
acousma
British Dictionary definitions for acorn worm
acorn worm
noun
any of various small burrowing marine animals of the genus Balanoglossus and related genera, having an elongated wormlike body with an acorn-shaped eversible proboscis at the head end: subphylum Hemichordata (hemichordates)