The Collaborative International Dictionary of English v.0.48:

Consider \Con*sid"er\ (k[o^]n*s[i^]d"[~e]r), v. t. [imp. & p. p.
   Considered (k[o^]n*s[i^]d"[~e]rd); p. pr. & vb. n.
   Considering.] [F. consid['e]rer, L. considerare,
   -sideratum, to consider, view attentively, prob. fr. con- +
   sidus, sideris, star, constellation; orig., therefore, to
   look at the stars. See Sidereal, and cf. Desire.]
   1. To fix the mind on, with a view to a careful examination;
      to think on with care; to ponder; to study; to meditate
      on.
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            I will consider thy testimonies.      --Ps. cxix.
                                                  95.
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            Thenceforth to speculations high or deep
            I turned my thoughts, and with capacious mind
            Considered all things visible.        --Milton.
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   2. To look at attentively; to observe; to examine.
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            She considereth a field, and buyeth it. --Prov.
                                                  xxxi. 16.
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   3. To have regard to; to take into view or account; to pay
      due attention to; to respect.
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            Consider, sir, the chance of war: the day
            Was yours by accident.                --Shak.
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            England could grow into a posture of being more
            united at home, and more considered abroad. --Sir W.
                                                  Temple.
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   4. To estimate; to think; to regard; to view.
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            Considered as plays, his works are absurd.
                                                  --Macaulay.
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   Note: The proper sense of consider is often blended with an
         idea of the result of considering; as, "Blessed is he
         that considereth the poor." --Ps. xli. 1.; i.e.,
         considers with sympathy and pity. "Which [services] if
         I have not enough considered." --Shak.; i.e., requited
         as the sufficient considering of them would suggest.
         "Consider him liberally." --J. Hooker.

   Syn: To ponder; weigh; revolve; study; reflect or meditate
        on; contemplate; examine. See Ponder.
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The Collaborative International Dictionary of English v.0.48:

Consider \Con*sid"er\, v. i.
   1. To think seriously; to make examination; to reflect; to
      deliberate.
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            We will consider of your suit.        --Shak.
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            'T were to consider too curiously, to consider so.
                                                  --Shak.
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            She wished she had taken a moment to consider,
            before rushing down stairs.           --W. Black
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   2. To hesitate. [Poetic & R.] --Dryden.
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WordNet (r) 3.0 (2006):

consider
    v 1: deem to be; "She views this quite differently from me"; "I
         consider her to be shallow"; "I don't see the situation
         quite as negatively as you do" [syn: see, consider,
         reckon, view, regard]
    2: give careful consideration to; "consider the possibility of
       moving" [syn: study, consider]
    3: take into consideration for exemplifying purposes; "Take the
       case of China"; "Consider the following case" [syn:
       consider, take, deal, look at]
    4: show consideration for; take into account; "You must consider
       her age"; "The judge considered the offender's youth and was
       lenient" [syn: consider, count, weigh]
    5: think about carefully; weigh; "They considered the
       possibility of a strike"; "Turn the proposal over in your
       mind" [syn: consider, debate, moot, turn over,
       deliberate]
    6: judge or regard; look upon; judge; "I think he is very
       smart"; "I believe her to be very smart"; "I think that he is
       her boyfriend"; "The racist conceives such people to be
       inferior" [syn: think, believe, consider, conceive]
    7: look at attentively [syn: regard, consider]
    8: look at carefully; study mentally; "view a problem" [syn:
       view, consider, look at]
    9: regard or treat with consideration, respect, and esteem;
       "Please consider your family"