The Collaborative International Dictionary of English v.0.48:

Advisement \Ad*vise"ment\ ([a^]d*v[imac]z"ment), n. [OE.
   avisement, F. avisement, fr. aviser. See Advise, and cf.
   Avisement.]
   [1913 Webster]
   1. Counsel; advice; information. [Archaic]
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            And mused awhile, waking advisement takes of what
            had passed in sleep.                  --Daniel.
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   2. Consideration; deliberation; consultation.
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            Tempering the passion with advisement slow.
                                                  --Spenser.
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WordNet (r) 3.0 (2006):

advisement
    n 1: careful consideration; "a little deliberation would have
         deterred them" [syn: deliberation, weighing,
         advisement]

Bouvier's Law Dictionary, Revised 6th Ed (1856):

ADVISEMENT. Consideration, deliberation, consultation; as the court holds
the case under advisement.