- caster (n.1)
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- "person or thing that casts," late 14c. (also sometimes castor), agent noun from cast (v.). Meaning "pepper shaker, small perforated container" is from 1670s, on notion of "throwing."
- caster (n.2)
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- "wheel and swivel attached to furniture," 1748, agent noun from cast (v.) in the old sense of "turn." Also sometimes castor.