The Collaborative International Dictionary of English v.0.48:

Distribution \Dis`tri*bu"tion\, n. [L. distributio: cf. F.
   distribution.]
   1. The act of distributing or dispensing; the act of dividing
      or apportioning among several or many; apportionment; as,
      the distribution of an estate among heirs or children.
      [1913 Webster]

            The phenomena of geological distribution are exactly
            analogous to those of geography.      --A. R.
                                                  Wallace.
      [1913 Webster]

   2. Separation into parts or classes; arrangement of anything
      into parts; disposition; classification.
      [1913 Webster]

   3. That which is distributed. "Our charitable distributions."
      --Atterbury.
      [1913 Webster]

   4. (Logic) A resolving a whole into its parts.
      [1913 Webster]

   5. (Print.) The sorting of types and placing them in their
      proper boxes in the cases.
      [1913 Webster]

   6. (Steam Engine) The steps or operations by which steam is
      supplied to and withdrawn from the cylinder at each stroke
      of the piston; viz., admission, suppression or cutting
      off, release or exhaust, and compression of exhaust steam
      prior to the next admission.
      [1913 Webster]

   Geographical distribution, the natural arrangements of
      animals and plants in particular regions or districts.

   Syn: Apportionments; allotment; dispensation; disposal;
        dispersion; classification; arrangement.
        [1913 Webster]

WordNet (r) 3.0 (2006):

distribution
    n 1: (statistics) an arrangement of values of a variable showing
         their observed or theoretical frequency of occurrence [syn:
         distribution, statistical distribution]
    2: the spatial or geographic property of being scattered about
       over a range, area, or volume; "worldwide in distribution";
       "the distribution of nerve fibers"; "in complementary
       distribution" [syn: distribution, dispersion] [ant:
       compactness, concentration, denseness, density,
       tightness]
    3: the act of distributing or spreading or apportioning
    4: the commercial activity of transporting and selling goods
       from a producer to a consumer

Moby Thesaurus II by Grady Ward, 1.0:

72 Moby Thesaurus words for "distribution":
   administration, allocation, allotment, apportionment, arrangement,
   array, arraying, assignment, attenuation, broadcast, broadcasting,
   cataloguing, circulation, circumfusion, classification,
   codification, collation, collocation, constitution, deployment,
   diffraction, diffusion, dilution, disbursal, disbursement,
   dispensation, dispersal, dispersion, disposal, disposition,
   dissemination, dissipation, divergence, division, dole, doling,
   doling out, evaporation, expansion, form, formation, formulation,
   fragmentation, giving out, grouping, issuance, marshaling, order,
   ordering, passing around, paying out, peppering, placement,
   propagation, publication, radiation, regimentation, scattering,
   scatterment, sequence, sharing, shotgun pattern, sowing,
   spattering, splay, spread, spreading, sprinkling, strewing,
   structuring, syntax, volatilization



The Jargon File (version 4.4.7, 29 Dec 2003):

distribution
 n.

    1. A software source tree packaged for distribution; but see kit. Since
    about 1996 unqualified use of this term often implies ?Linux
    distribution?. The short form distro is often used for this sense.

    2. A vague term encompassing mailing lists and Usenet newsgroups (but not 
    BBS fora); any topic-oriented message channel with multiple recipients.

    3. An information-space domain (usually loosely correlated with geography)
    to which propagation of a Usenet message is restricted; a
    much-underutilized feature.


The Free On-line Dictionary of Computing (30 December 2018):

distribution

   1.  A software source tree packaged for
   distribution; but see kit.

   2.  A vague term encompassing mailing lists and
   Usenet newsgroups (but not BBS fora); any
   topic-oriented message channel with multiple recipients.

   3.  An information-space domain (usually loosely
   correlated with geography) to which propagation of a Usenet
   message is restricted; a much-underused feature.

   [Jargon File]