What does "ligula" mean?

Ligula: (Zoöl.) (a) The central process, or front edge, of the labium of insects. It sometimes serves as a tongue or proboscis, as in bees. [See Illust. under Labium, and Hymenoptera.] (b) A tongue-shaped lobe of the parapodia of annelids. See Parapodium.

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