[1] : The Collaborative International Dictionary of English v.0.48

unlawful \unlaw"ful\, a.
   not lawful; contrary to law. -- unlaw"fully, adv. --
   unlaw"fulness, n.
   1913 webster

   unlawful assembly. law see under assembly.
      1913 webster
see also:
unlaw"fully unlaw"fulness unlawful assembly assembly 

[2] : WordNet (r) 2.0

unlawful
     adj 1: not conforming to legality, moral law, or social convention;
            "an unconventional marriage"; "improper banking
            practices" syn: improper, unconventional
     2: contrary to or prohibited by or defiant of law; "unlawful
        measures"; "unlawful money"; "unlawful hunters" ant: lawful
     3: not morally right or permissible; "unlawful love"
     4: having no legally established claim; "the wrongful heir to
        the throne" syn: wrongful
     5: contrary to or forbidden by law; "an illegitimate seizure of
        power"; "illicit trade"; "an outlaw strike"; "unlawful
        measures" syn: illegitimate, illicit, outlawa, outlawed
see also:
improper unconventional lawful wrongful illegitimate illicit 
outlawa outlawed 

[3] : Moby Thesaurus II by Grady Ward, 1.0

99 moby thesaurus words for "unlawful":
   aberrant, abnormal, abominable, actionable, against the law,
   anarchic, anarchistic, anomic, atrocious, banned, barred,
   black-market, bootleg, chargeable, contraband, contrary to law,
   criminal, delinquent, deviant, disgraceful, evil, exceptionable,
   felonious, flawed, forbade, forbid, forbidden, hardly the thing,
   ignominious, illegal, illegitimate, illicit, impermissible,
   improper, inappropriate, incorrect, indecorous, infamous,
   iniquitous, interdicted, intolerable, irregular, justiciable,
   lawless, nefarious, nonconstitutional, nonlegal, nonlicit,
   nonpermissible, not done, not permitted, not the thing,
   objectionable, off limits, off-base, off-color, out of bounds,
   out-of-line, outlaw, outlawed, prohibited, proscribed, punishable,
   ruled out, sacrilegious, scandalous, shameful, shameless, sinful,
   taboo, tabooed, terrible, triable, unallowed, unauthorized,
   unconstitutional, under the ban, under the table,
   under-the-counter, under-the-table, undue, unfit, unfitting,
   unlicensed, unofficial, unpermissible, unrighteous, unsanctioned,
   unseemly, unstatutory, unsuitable, untouchable, unwarrantable,
   unwarranted, verboten, vetoed, wicked, wrong, wrongful

[4] : Bouvier's Law Dictionary, Revised 6th Ed (1856)

unlawful. that which is contrary to law. 
     2. there are two kinds of contracts which are unlawful; those which are 
void, and those which are not. when the law expressly prohibits the 
transaction in respect of which the agreement is entered into and declares 
it to be void, it is absolutely so. 3 binn. r. 533. but when it is merely 
prohibited, without being made void, although unlawful, it is not void. 12 
serg.  rawle, 237; chitty, contr. 230; 23 amer. jur. 1 to 23; 1 mod. 35; 8 
east, r. 236, 237; 3 taunt. r. 244; hob. 14. vide condition; void. 

Unlawful >> U Words
Unlawful, definition of term: Unlawful
unlawful_pag1.html