caddisworm

American  

[kad-is-wurm] / ˈkæd ɪsˌwɜrm /

noun

1. the aquatic larva of a caddisfly, having an armored head and a pair of abdominal hooks, and typically living in a case built from sand or plant debris.

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Etymology

Origin of caddisworm

1615–25; caddis (perhaps plural, taken as singular, of caddy, diminutive of cad larva, ghost) + worm