Definition of plumicome in US English:

plumicome

noun

Zoology
rare
  • In siliceous sponges: a type of six-rayed spicule (hexaster) each of whose rays branches to form a feather-like tuft.

Origin

Late 19th century. From classical Latin plūmi-, combining form (in e.g. plūmipēs) of plūma + coma the hair of the head.

Pronunciation

plumicome

/ˈpluːmɪkəʊm/