The Collaborative International Dictionary of English v.0.48:

Common \Com"mon\, a. [Compar. Commoner; superl. Commonest.]
   [OE. commun, comon, OF. comun, F. commun, fr. L. communis;
   com- + munis ready to be of service; cf. Skr. mi to make
   fast, set up, build, Goth. gamains common, G. gemein, and E.
   mean low, common. Cf. Immunity, Commune, n. & v.]
   1. Belonging or relating equally, or similarly, to more than
      one; as, you and I have a common interest in the property.
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            Though life and sense be common to men and brutes.
                                                  --Sir M. Hale.
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   2. Belonging to or shared by, affecting or serving, all the
      members of a class, considered together; general; public;
      as, properties common to all plants; the common schools;
      the Book of Common Prayer.
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            Such actions as the common good requireth. --Hooker.
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            The common enemy of man.              --Shak.
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   3. Often met with; usual; frequent; customary.
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            Grief more than common grief.         --Shak.
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   4. Not distinguished or exceptional; inconspicuous; ordinary;
      plebeian; -- often in a depreciatory sense.
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            The honest, heart-felt enjoyment of common life.
                                                  --W. Irving.
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            This fact was infamous
            And ill beseeming any common man,
            Much more a knight, a captain and a leader. --Shak.
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            Above the vulgar flight of common souls. --A.
                                                  Murphy.
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   5. Profane; polluted. [Obs.]
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            What God hath cleansed, that call not thou common.
                                                  --Acts x. 15.
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   6. Given to habits of lewdness; prostitute.
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            A dame who herself was common.        --L'Estrange.
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   Common bar (Law) Same as Blank bar, under Blank.

   Common barrator (Law), one who makes a business of
      instigating litigation.

   Common Bench, a name sometimes given to the English Court
      of Common Pleas.

   Common brawler (Law), one addicted to public brawling and
      quarreling. See Brawler.

   Common carrier (Law), one who undertakes the office of
      carrying (goods or persons) for hire. Such a carrier is
      bound to carry in all cases when he has accommodation, and
      when his fixed price is tendered, and he is liable for all
      losses and injuries to the goods, except those which
      happen in consequence of the act of God, or of the enemies
      of the country, or of the owner of the property himself.


   Common chord (Mus.), a chord consisting of the fundamental
      tone, with its third and fifth.

   Common council, the representative (legislative) body, or
      the lower branch of the representative body, of a city or
      other municipal corporation.

   Common crier, the crier of a town or city.

   Common divisor (Math.), a number or quantity that divides
      two or more numbers or quantities without a remainder; a
      common measure.

   Common gender (Gram.), the gender comprising words that may
      be of either the masculine or the feminine gender.

   Common law, a system of jurisprudence developing under the
      guidance of the courts so as to apply a consistent and
      reasonable rule to each litigated case. It may be
      superseded by statute, but unless superseded it controls.
      --Wharton.

   Note: It is by others defined as the unwritten law
         (especially of England), the law that receives its
         binding force from immemorial usage and universal
         reception, as ascertained and expressed in the
         judgments of the courts. This term is often used in
         contradistinction from statute law. Many use it to
         designate a law common to the whole country. It is also
         used to designate the whole body of English (or other)
         law, as distinguished from its subdivisions, local,
         civil, admiralty, equity, etc. See Law.

   Common lawyer, one versed in common law.

   Common lewdness (Law), the habitual performance of lewd
      acts in public.

   Common multiple (Arith.) See under Multiple.

   Common noun (Gram.), the name of any one of a class of
      objects, as distinguished from a proper noun (the name of
      a particular person or thing).

   Common nuisance (Law), that which is deleterious to the
      health or comfort or sense of decency of the community at
      large.

   Common pleas, one of the three superior courts of common
      law at Westminster, presided over by a chief justice and
      four puisne judges. Its jurisdiction is confined to civil
      matters. Courts bearing this title exist in several of the
      United States, having, however, in some cases, both civil
      and criminal jurisdiction extending over the whole State.
      In other States the jurisdiction of the common pleas is
      limited to a county, and it is sometimes called a county
      court. Its powers are generally defined by statute.

   Common prayer, the liturgy of the Church of England, or of
      the Protestant Episcopal church of the United States,
      which all its clergy are enjoined to use. It is contained
      in the Book of Common Prayer.

   Common school, a school maintained at the public expense,
      and open to all.

   Common scold (Law), a woman addicted to scolding
      indiscriminately, in public.

   Common seal, a seal adopted and used by a corporation.

   Common sense.
      (a) A supposed sense which was held to be the common bond
          of all the others. [Obs.] --Trench.
      (b) Sound judgment. See under Sense.

   Common time (Mus.), that variety of time in which the
      measure consists of two or of four equal portions.

   In common, equally with another, or with others; owned,
      shared, or used, in community with others; affecting or
      affected equally.

   Out of the common, uncommon; extraordinary.

   Tenant in common, one holding real or personal property in
      common with others, having distinct but undivided
      interests. See Joint tenant, under Joint.

   To make common cause with, to join or ally one's self with.

   Syn: General; public; popular; national; universal; frequent;
        ordinary; customary; usual; familiar; habitual; vulgar;
        mean; trite; stale; threadbare; commonplace. See
        Mutual, Ordinary, General.
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The Collaborative International Dictionary of English v.0.48:

Divisor \Di*vi"sor\, n. [L., fr. dividere. See Divide.]
   (Math.)
   The number by which the dividend is divided.
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   Common divisor. (Math.) See under Common, a.
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WordNet (r) 3.0 (2006):

common divisor
    n 1: an integer that divides two (or more) other integers evenly
         [syn: common divisor, common factor, common measure]