The Collaborative International Dictionary of English v.0.48:

Defense \De*fense"\, Defence \De*fence"\, n. [F. d['e]fense, OF.
   defense, fem., defens, masc., fr. L. defensa (cf. LL.
   defensum), from defendere. See Defend, and cf. Fence.]
   1. The act of defending, or the state of being defended;
      protection, as from violence or danger.
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            In cases of defense 't is best to weigh
            The enemy more mighty than he seems.  --Shak.
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   2. That which defends or protects; anything employed to
      oppose attack, ward off violence or danger, or maintain
      security; a guard; a protection.
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            War would arise in defense of the right. --Tennyson.
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            God, the widow's champion and defense. --Shak.
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   3. Protecting plea; vindication; justification.
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            Men, brethren, and fathers, hear ye my defense.
                                                  --Acts xxii.
                                                  1.
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   4. (Law) The defendant's answer or plea; an opposing or
      denial of the truth or validity of the plaintiff's or
      prosecutor's case; the method of proceeding adopted by the
      defendant to protect himself against the plaintiff's
      action.
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   5. Act or skill in making defense; defensive plan or policy;
      practice in self defense, as in fencing, boxing, etc.
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            A man of great defense.               --Spenser.
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            By how much defense is better than no skill. --Shak.
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   6. Prohibition; a prohibitory ordinance. [Obs.]
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            Severe defenses . . . against wearing any linen
            under a certain breadth.              --Sir W.
                                                  Temple.
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The Collaborative International Dictionary of English v.0.48:

Defense \De*fense"\, v. t.
   To furnish with defenses; to fortify. [Obs.] [Written also
   defence.]
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         Better manned and more strongly defensed. --Hales.
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