The Collaborative International Dictionary of English v.0.48:

Moral \Mor"al\, a. [F., fr. It. moralis, fr. mos, moris, manner,
   custom, habit, way of life, conduct.]
   1. Relating to duty or obligation; pertaining to those
      intentions and actions of which right and wrong, virtue
      and vice, are predicated, or to the rules by which such
      intentions and actions ought to be directed; relating to
      the practice, manners, or conduct of men as social beings
      in relation to each other, as respects right and wrong, so
      far as they are properly subject to rules.
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            Keep at the least within the compass of moral
            actions, which have in them vice or virtue.
                                                  --Hooker.
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            Mankind is broken loose from moral bands. --Dryden.
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            She had wandered without rule or guidance in a moral
            wilderness.                           --Hawthorne.
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   2. Conformed to accepted rules of right; acting in conformity
      with such rules; virtuous; just; as, a moral man. Used
      sometimes in distinction from religious; as, a moral
      rather than a religious life.
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            The wiser and more moral part of mankind. --Sir M.
                                                  Hale.
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   3. Capable of right and wrong action or of being governed by
      a sense of right; subject to the law of duty.
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            A moral agent is a being capable of those actions
            that have a moral quality, and which can properly be
            denominated good or evil in a moral sense. --J.
                                                  Edwards.
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   4. Acting upon or through one's moral nature or sense of
      right, or suited to act in such a manner; as, a moral
      arguments; moral considerations. Sometimes opposed to
      material and physical; as, moral pressure or support.
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   5. Supported by reason or probability; practically
      sufficient; -- opposed to legal or demonstrable; as, a
      moral evidence; a moral certainty.
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   6. Serving to teach or convey a moral; as, a moral lesson;
      moral tales.
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   Moral agent, a being who is capable of acting with
      reference to right and wrong.

   Moral certainty, a very high degree or probability,
      although not demonstrable as a certainty; a probability of
      so high a degree that it can be confidently acted upon in
      the affairs of life; as, there is a moral certainty of his
      guilt.

   Moral insanity, insanity, so called, of the moral system;
      badness alleged to be irresponsible.

   Moral philosophy, the science of duty; the science which
      treats of the nature and condition of man as a moral
      being, of the duties which result from his moral
      relations, and the reasons on which they are founded.

   Moral play, an allegorical play; a morality. [Obs.]

   Moral sense, the power of moral judgment and feeling; the
      capacity to perceive what is right or wrong in moral
      conduct, and to approve or disapprove, independently of
      education or the knowledge of any positive rule or law.

   Moral theology, theology applied to morals; practical
      theology; casuistry.
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Bouvier's Law Dictionary, Revised 6th Ed (1856):

MORAL INSANITY, med. jur. A term used by medical men, which has not yet
acquired much reputation in the courts. Moral insanity is said to consist in
a morbid perversion of the moral feelings, affections, inclinations, temper,
habits, and moral dispositions, without any notable lesion of the intellect,
or knowing and reasoning faculties, and particularly without any maniacal
hallucination. Prichard, art. Insanity, in Cyclopaedia of Practical Medicine
     2. It is contended that some human beings exist, who, in consequence of
a deficiency in the moral organs, are as blind to the dictates of justice,
as others are deaf to melody. Combe, Moral Philosophy, Lect. 12.
     3. In some, this species of malady is said to display itself in an
irresistible propensity to commit murder; in others, to commit theft, or
arson. Though most persons afflicted with this malady commit such crimes,
there are others whose disease is manifest in nothing but irascibility.
Annals D'Hygiene tom. i. p. 284. Many are subjected to melancholy, and
dejection, without any delusion or illusion. This, perhaps without full
consideration, has been judicially declared to be a "groundless theory." The
courts, and law writers, have not given it their full assent. 1 Chit. Med.
Jur. 352; 1 Beck, Med. Jur. 553 Ray, Med. Jur. Prel. Views, Sec. 23, p. 49.