| a screen or mat covered with a dark material for shielding a camera lens from excess light or glare. |
| a calculus or concretion found in the stomach or intestines of certain animals, esp. ruminants, formerly reputed to be an effective remedy for poison. |
chiton
any of numerous flattened, bilaterally symmetrical marine mollusks, worldwide in distribution but most abundant in warm regions. The approximately 600 species are usually placed in the class Placophora, Polyplacophora, or Loricata (phylum Mollusca).
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