vinculum
From ZooTerms (Dictionary of Invertebrate Zoology)
vinculum (noun; plural -la; Latin vinculum, anything used for binding): 1. Anything used to bond structures together.
2. (Arthropoda: Insecta) In male Lepidoptera, an U-shaped genital plate, dorsally articulating with the pedunculus and midventrally forming a saccus.
3. (Mollusca: Bivalvia) A shelly material between the basic dental structures of the shell.
