Icon wiki:
Greek , eikon, "image") is an image, picture, or representation; it is a sign or likeness that stands for an object by signifying or representing it, or by analogy, as in semiotics; in computers an icon is a symbol on the monitor used to signify a command; by extension, icon is also used, particularly in modern popular culture, in the general sense of symbol â i.e. a name, face, picture or even a person readily recognized as having some well-known significance or embodying certain qualities.
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Skull wiki:
l, or cranium, is a bony structure of Craniates which serves as the general framework for a head. The skull supports the structures of the face and protects the brain against injury.
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