1. The outermost layer of the skin of vertebrates; epidermis.
2. The strip of hardened skin at the base and sides of a fingernail or toenail.
3. Dead or cornified epidermis.
4. Zoology The noncellular, hardened or membranous protective covering of many invertebrates, such as the transparent membrane that covers annelids.
5. Botany The layer of cutin covering the epidermis of the aerial parts of plants.
[Latin cutīcula, diminutive of cutis, skin; see (s)keu- in the Appendix of Indo-European roots.]
cu·ticu·lar (-tĭkyə-lər) adj.
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