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

illegal \ille"gal\, a. pref. il- not + legal: cf. f.
   ill'egal.
   not according to, or authorized by, law; specif., contrary
   to, or in violation of, human law; unlawful; illicit; hence,
   immoral; as, an illegal act; illegal trade; illegal love.
   --bp. burnet.
   1913 webster

[2] : WordNet (r) 2.0

illegal
     adj : prohibited by law or by official or accepted rules; "an
           illegal chess move" ant: legal
see also:
legal 

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

105 moby thesaurus words for "illegal":
   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, felonious,
   flawed, forbade, forbid, forbidden, hardly the thing, hot,
   ignominious, illegitimate, illicit, impermissible, improper,
   inappropriate, incorrect, indecorous, inequitable, infamous,
   iniquitous, interdicted, irregular, justiciable, lawless,
   nonconstitutional, nonlegal, nonlicit, nonpermissible, not done,
   not permitted, not the thing, 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, unbalanced, unconstitutional,
   under the ban, under-the-counter, under-the-table, undeserved,
   undue, unequal, unequitable, uneven, unfit, unfitting, unjust,
   unlawful, unlicensed, unmeet, unmerited, unofficial, unpermissible,
   unrighteous, unrightful, unsanctioned, unseemly, unstatutory,
   unsuitable, untouchable, unwarrantable, unwarranted, verboten,
   vetoed, wicked, wrong, wrongful

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

illegal. contrary to law; unlawful.
     2. it is a general rule, that the law will never give its aid to a 
party who has entered into an illegal contract, whether the same be in 
direct violation of a statute, against public policy, or opposed to public 
morals. nor to a contract which is fraudulent, which affects the defendant 
or a third person. 
     3. a contract in violation of a statute is absolutely void, and, 
however disguised, it will be set aside, for no form of expression can 
remove the substantial defect inherent in the nature of the transaction; the 
courts will investigate the real object of the contracting parties, and if 
that be repugnant to the law, it will vitiate the transaction. 
     4. contracts against the public policy of the law, are equally void as 
if they were in violation of a public statute; a contract not to marry any 
one, is therefore illegal and void. see void. 
     5. a contract against the purity of manners is also illegal; as, for 
example, a agreement to cohabit unlawfully with another, is therefore void; 
but a bond given for past cohabitation, being considered as remuneration for 
past injury, is binding. 4 bouv. inst. n. 3853. 
     6. all contracts which have for their object, or which may in their 
consequences, be injurious to third persons, altogether unconnected with 
them, are in general illegal and void. of the first, an example may be found 
in the case where a sheriff's officer received a sum of money from a 
defendant for admitting to bail, and agreed to pay the bail, part of the 
money which was so exacted. 2 burr. 924. the case of a wager between two 
persons, as to the character of a third, is an example of the second class. 
cowp. 729; 4 camp. 152; 1 rawle, 42; 1 b.  a. 683. vide illicit; unlawful. 

Illegal >> I Words
Illegal, definition of term: Illegal
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