4
sham(adjective, fake, deception, false, inferior)
4
unauthentic(fake, false, bogus)
4
unjust(adjective, unreasonable, extreme, improper, stiff)
4
verboten(adjective, illegal)
4
wicked(adjective, wrong, legal, illegal, unlawful)
4
wrong(adjective, corrupt, vicious, dishonest, improper)
3
against the law(expression, adjective, idiom, wrong, illegal)
3
base-born
3
bastardy
3
clandestine(adjective, secret, sly)
3
colorable
3
crooked(adjective, wrong, irregular, unwarranted, illegal)
3
foul
3
fraudulent(deception, hidden, sly)
3
immoral(adjective, wrong, illegal, unlawful)
3
impermissible
3
pretended(fake, deception, false, bogus)
3
prohibited(adjective, illegality)
3
undue(adjective, extreme, improper, senseless, excessive)
3
unlicensed(adjective, illegal)
11 years ago|17k views|share |citing 
APASmart Define. (2015). illegitimate thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/illegitimate/thesaurus/synonyms
ChicagoSmart Define. 2015. "illegitimate thesaurus" https://smartdefine.org/illegitimate/thesaurus/synonyms (accessed September 24, 2026).
HarvardSmart Define 2015, illegitimate thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/illegitimate/thesaurus/synonyms>.
MLASmart Define. "illegitimate thesaurus" 10 April 2015. Web. 24 September 2026. <https://smartdefine.org/illegitimate/thesaurus/synonyms>