strobila

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A part or structure that buds to form a series of segments, especially.
• noun The body of a tapeworm behind the scolex, consisting of a series of proglottids.
• noun The stack of disklike segments produced by the polyps of certain jellyfishes, which separates into immature medusae.

from The Century Dictionary.

• noun In zoology: In Hydrozoa, a stage in the development of a discophoran, supervening upon the scyphistoma or hydra-tuba stage by the development of ephyræ, and before these become detached from one another and from the stalk upon which they grow. See ephyra, 1, and scyphistoma.
• noun In Vermes, a segmented tapeworm; the chain of zooids formed by a scolex and the proglottides which have successively budded from it.
• noun [capitalized] A supposed genus of acalephs, based on the strobiliform stage of certain hydrozoans.
• noun [capitalized] In entomology, a genus of lepidopterous insects.

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

• noun A form of the larva of certain Discophora in a state of development succeeding the scyphistoma. The body of the strobila becomes elongated, and subdivides transversely into a series of lobate segments which eventually become ephyræ, or young medusæ.
• noun A mature tapeworm.

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

• noun zoology The jointed series of segments of the body of a tapeworm, posterior to the unjointed collum.