the larva of moths of the family Psychidae, which forms a protective case of silk covered with grass, leaves, etc
2. bagworm moth
bagworm in American English
(ˈbægˌwɜrm)
US
noun
any of a family (Psychidae) of moths with larvae that build cocoons shaped like bags and feed on the leaves of various trees: the wingless, legless adult females continue to live within the casing