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

illicit \illic"it\, a. l. illicitus; pref. il- not + licitus,
   p. p. of licere to be allowed or permitted: cf. f. illicite.
   see in- not, and license.
   not permitted or allowed; prohibited; unlawful; as, illicit
   trade; illicit intercourse; illicit pleasure.
   1913 webster

         one illicit . . . transaction always leads to another.
                                                  --burke.
   -- illic"itly, adv. -- illic"itness, n.
   1913 webster
see also:
in- license illic"itly illic"itness 

[2] : WordNet (r) 2.0

illicitness
     n : the quality of not conforming strictly to law ant: licitness
see also:
licitness 

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