The Collaborative International Dictionary of English v.0.48:

Factious \Fac"tious\ a. [L. factiosus: cf. F. factieux.]
   1. Given to faction; addicted to form parties and raise
      dissensions, in opposition to government or the common
      good; turbulent; seditious; prone to clamor against public
      measures or men; -- said of persons.
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            Factious for the house of Lancaster.  --Shak.
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   2. Pertaining to faction; proceeding from faction;
      indicating, or characterized by, faction; -- said of acts
      or expressions; as, factious quarrels.
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            Headlong zeal or factious fury.       --Burke.
      -- Fac"tious*ly, adv. -- Fac"tious*ness, n.
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