Definition of siphuncle in English:

siphuncle

Syllabification: si·phun·cle
Pronunciation: /ˈsīfəNGkəl
 
/

noun

Zoology
  • (In shelled cephalopods such as nautiloids and ammonoids) a calcareous tube containing living tissue running through all the shell chambers, serving to pump fluid out of vacant chambers in order to adjust buoyancy.
    More example sentences
    • The dorsal siphuncles of the Clymeniida tend to be larger than the ventral siphuncles of other ammonoid clades.
    • Outwardly indistinguishable from other ammonoids, clymeniids are distinguished internally by their dorsal siphuncle, contrasted to a ventral siphuncle in almost all other ammonoids.
    • Given that the shell that covers the siphuncle is its only permeable surface, the interchange of fluids can take place only through this structure.

Origin

mid 18th century: from Latin siphunculus 'small tube'.

More definitions of siphuncle

Definition of siphuncle in:

Get more from Oxford Dictionaries

Subscribe to remove adverts and access premium resources

Word of the day kerf
Pronunciation: kəːf
noun
a slit made by cutting with a saw