spicule

noun

Etymology: From Latin spīculum.

1. A sharp, needle-like piece.
2. A tiny glass flake formed during the manufacture of glass vials.
3. Any of many needle-like crystalline structures that provide skeletal support in marine invertebrates like sponges.

   “Tear it up, and put a fragment under the microscope, and, wonder of wonders! see the maze of geometric forms exhibited in the bones of the creature; for who can help regarding the spicules as bones, even though a sponge be invertebrate?”

4. A needle-like mating structure found only in male nematodes.
5. A jet of matter ejected from the photosphere of the sun.
6. A small spike of flowers.
7. A unit of mass equal to 125 pounds.