sericterium

/ˌsɛrɪkˈtɪriəm/
noun
  1. A silk-producing gland or organ in insects such as silkworms and spiders.
    • Spiders have a modified sericterium that allows them to spin different types of silk.
    • In caterpillars, the sericterium is connected to the spinneret, which shapes the silk.
    • The silkworm's sericterium produces the liquid silk that hardens into a thread.