n. pl. spic·ules also spic·u·lae (-yə-lē) 1. A small needlelike structure or part, such as one of the silicate or calcium carbonate processes supporting the soft tissue of certain invertebrates, especially sponges. 2. Astronomy A spike-shaped formation emanating from the ionized gas of the solar photosphere. [Latin spīculum; see SPICULUM.] spicu·lar (-yə-lər), spicu·late (-yə-lĭt, -lāt′) adj. |
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