The Collaborative International Dictionary of English v.0.48:

Swart \Swart\, a. [OE. swart, AS. sweart black; akin to OFries,
   OS. & LG. swart, D. zwart, G. schwartz, OHG. swarz, Icel.
   svarir, Sw. svart, Dan. sort, Goth. swarts; cf. L. sordes
   dirt, sordere to be dirty. Cf. Sordid, Surd.]
   1. Of a dark hue; moderately black; swarthy; tawny. "Swart
      attendants." --Trench. "Swart savage maids." --Hawthorne.
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            A nation strange, with visage swart.  --Spenser.
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   2. Gloomy; malignant. [Obs.] --Milton.
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   Swart star, the Dog Star; -- so called from its appearing
      during the hot weather of summer, which makes swart the
      countenance. [R.] --Milton.
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