Source : Webster's Revised Unabridged Dictionary (1913)

Spicula \Spic"u*la\, n.; pl. {Spicul[ae]}. [NL., dim. of L.
   spica a spike, ear.] (Bot.)
   (a) A little spike; a spikelet.
   (b) A pointed fleshy appendage.

Spiculum \Spic"u*lum\, n.; pl. {Spicula}. [L., a little point.]
   (Zo["o]l.)
   Same as {Spicule}.

Source : WordNet®

spiculum
     n : small pointed structure serving as a skeletal element in
         various marine and freshwater invertebrates e.g. sponges
         and corals [syn: {spicule}]
     [also: {spicula} (pl)]

spicula
     See {spiculum}