sagittocyst

from The Century Dictionary.

• noun One of the cutaneous cells of turbellarian worms, containing rhabdites.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Zoöl.) A defensive cell containing a minute rodlike structure which may be expelled. Such cells are found in certain Turbellaria.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun A capsule having a spindle-like needle produced by epidermal cells of certain turbellarians.