The Collaborative International Dictionary of English v.0.48:

Restriction \Re*stric"tion\, n. [F. restriction, L. restrictio.]
   1. The act of restricting, or state of being restricted;
      confinement within limits or bounds.
      [1913 Webster]

            This is to have the same restriction with all other
            recreations,that it be made a divertisement. --Giv.
                                                  of Tonque.
      [1913 Webster]

   2. That which restricts; limitation; restraint; as,
      restrictions on trade.
      [1913 Webster]

WordNet (r) 3.0 (2006):

restriction
    n 1: a principle that limits the extent of something; "I am
         willing to accept certain restrictions on my movements"
         [syn: restriction, limitation]
    2: an act of limiting or restricting (as by regulation) [syn:
       limitation, restriction]
    3: the act of keeping something within specified bounds (by
       force if necessary); "the restriction of the infection to a
       focal area" [syn: restriction, confinement]

Moby Thesaurus II by Grady Ward, 1.0:

126 Moby Thesaurus words for "restriction":
   allowance, arrest, arrestation, arrestment, ban, bar, barring,
   blockade, blockage, blocking, boundary, bounds, boycott, brake,
   caging, cession, check, circumscription, clogging, closeness,
   closing up, closure, concession, condition, confinement,
   constraint, constriction, continence, control, cramp, cramping,
   crowdedness, curb, debarment, debarring, delay, demarcation,
   detainment, detention, discipline, embargo, exception, exclusion,
   exemption, extenuating circumstances, fixation, foot-dragging,
   grain of salt, grant, hair, hairbreadth, hairsbreadth, hampering,
   hedge, hedging, hindering, hindrance, holdback, holdup, impediment,
   impoundment, inadmissibility, incapaciousness, incommodiousness,
   inhibition, injunction, interference, interruption, let, limit,
   limitation, lockout, lockup, mental reservation, moderation,
   modification, narrow gauge, narrowing, narrowness, nearness,
   negativism, nonadmission, nuisance value, obstruction,
   obstructionism, occlusion, omission, opposition, penning,
   preclusion, prescription, prohibition, proscription, provision,
   proviso, qualification, rejection, relegation, repression,
   repudiation, reservation, resistance, restrain, restraint,
   restrictedness, retardation, retardment, salvo, setback,
   slenderness, special case, special treatment, specialness,
   specification, squeeze, stint, stipulation, straitness,
   stranglehold, strictness, stricture, suppression, taboo,
   tight squeeze, tightness, waiver



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

restriction
 n.

    A bug or design error that limits a program's capabilities, and which is
    sufficiently egregious that nobody can quite work up enough nerve to
    describe it as a feature. Often used (esp. by marketroid types) to make
    it sound as though some crippling bogosity had been intended by the
    designers all along, or was forced upon them by arcane technical
    constraints of a nature no mere user could possibly comprehend (these
    claims are almost invariably false).

    Old-time hacker Joseph M. Newcomer advises that whenever choosing a
    quantifiable but arbitrary restriction, you should make it either a power
    of 2 or a power of 2 minus 1. If you impose a limit of 107 items in a list,
    everyone will know it is a random number ? on the other hand, a limit of 15
    or 16 suggests some deep reason (involving 0- or 1-based indexing in
    binary) and you will get less flamage for it. Limits which are round
    numbers in base 10 are always especially suspect.


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

restriction

   A bug or design error that limits a program's capabilities,
   and which is sufficiently egregious that nobody can quite work
   up enough nerve to describe it as a feature.  Often used
   (especially by marketroid types) to make it sound as though
   some crippling bogosity had been intended by the designers all
   along, or was forced upon them by arcane technical constraints
   of a nature no mere user could possibly comprehend (these
   claims are almost invariably false).

   Old-time hacker Joseph M. Newcomer advises that whenever
   choosing a quantifiable but arbitrary restriction, you should
   make it either a power of 2 or a power of 2 minus 1.  If you
   impose a limit of 17 items in a list, everyone will know it is
   a random number - on the other hand, a limit of 15 or 16
   suggests some deep reason (involving 0- or 1-based indexing in
   binary) and you will get less flamage for it.  Limits which
   are round numbers in base 10 are always especially suspect.

   [Jargon File]