spicule Meaning, Definition & Usage

  1. noun small pointed structure serving as a skeletal element in various marine and freshwater invertebrates e.g. sponges and corals
    spiculum.

WordNet

Spic"ule noun
Etymology
L. spiculum a little point, a dart.
Definitions
  1. A minute, slender granule, or point.
  2. (Bot.) Same as Spicula.
  3. (Zoöl.) Any small calcareous or siliceous body found in the tissues of various invertebrate animals, especially in sponges and in most Alcyonaria. ✍ Spicules vary exceedingly in size and shape, and some of those found in siliceous sponges are very complex in structure and elegant in form. They are of great use in classification.

Webster 1913