The Collaborative International Dictionary of English v.0.48:

Saturnine \Sat"ur*nine\, a. [L. Saturnus the god Saturn, also,
   the planet Saturn: cf. F. saturnin of or pertaining to lead
   (Saturn, in old chemistry, meaning lead), saturnien
   saturnine, saturnian. See Saturn.]
   1. Born under, or influenced by, the planet Saturn.
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   2. Heavy; grave; gloomy; dull; -- the opposite of
      mercurial; as, a saturnine person or temper. --Addison.
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   3. (Old Chem.) Of or pertaining to lead; characterized by, or
      resembling, lead, which was formerly called Saturn.
      [Archaic]
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   Saturnine colic (Med.), lead colic.
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