What is the meaning of Spicule?

A sharp, needle-like piece.

A tiny glass flake formed during the manufacture of glass vials

Any of many needle-like crystalline structures that provide skeletal support in marine invertebrates like sponges.

A needle-like mating structure found only in male nematodes.

A jet of matter ejected from the photosphere of the sun.

A small spike of flowers.

spicule

Source: wiktionary.org