The Collaborative International Dictionary of English v.0.48:

Regardless \Re*gard"less\, a.
   1. Having no regard; heedless; careless; as, regardless of
      life, consequences, dignity.
      [1913 Webster]

            Regardless of the bliss wherein he sat. --Milton.
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   2. Not regarded; slighted. [R.] --Spectator.
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   Syn: Heedless; negligent; careless; indifferent; unconcerned;
        inattentive; unobservant; neglectful.
        [1913 Webster] -- Re*gard"less*ly, adv. --
        Re*gard"less*ness, n.
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