siphuncle(redirected from siphuncles)
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A tubelike structure in the body of a shelled cephalopod, such as a nautilus, extending through each chamber of the shell.
[Latin sīphunculus, diminutive of sīphō, sīphōn-, siphon; see siphon.]
si·phun′cu·lar (-kyə-lər), si·phun′cu·late (-lĭt) adj.
1. (Zoology) (in certain cephalopods) a small tube that connects shell-chambers
2. (Zoology) (of aphids) a small siphon on the abdomen by which an aphid emits sticky liquid that acts as an alarm pheromone