permissible

from WordNet (r) 3.0 (2006)

permissible
    adj 1: that may be permitted especially as according to rule;
           "permissible behavior in school"; "a permissible tax
           deduction" [syn: {permissible}, {allowable}] [ant:
           {impermissible}]
    2: that may be accepted or conceded; "a kind of speculation that
       was permissible in cosmology but inadmissible in medicine"

from The Collaborative International Dictionary of English v.0.48

Permissible \Per*mis"si*ble\, a.
   That may be permitted; allowable; admissible. --
   {Per*mis"si*ble*ness}, n. -- {Per*mis"si*bly}, adv.
   [1913 Webster]

from Moby Thesaurus II by Grady Ward, 1.0

31 Moby Thesaurus words for "permissible":
      OK, acceptable, admissible, all right, allowable, allowed,
      approved, authorized, bearable, endorsed, excusable, justifiable,
      kosher, lawful, legal, legit, legitimate, legitimized, licit, okay,
      pardonable, permitted, proper, sanctionable, sanctioned, tolerable,
      tolerated, unforbidden, unprohibited, venial, warrantable

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