Definition of polysiphonic in US English:

polysiphonic

adjective

Zoology
  • Of the hydrocaulus of a colonial hydroid: composed of two or more tubes fused together.

Origin

Late 19th century; earliest use found in Adam Sedgwick (1854–1913), zoologist. From poly- + siphonic.

Pronunciation

polysiphonic

/ˌpɒlɪsʌɪˈfɒnɪk/