illegitimate

Something illegitimate is unlawful, or improper. If you're a doctor, even a great doctor, but you were never certified by the medical board, then you're an illegitimate doctor.

Illegitimate has the root for "law" in it, and something illegitimate is outside the law or custom. A child not born to married parents is known as an illegitimate child, although so many people are making different choices about how to raise families, that the stigma is dropping away, especially if the child isn't the result of philandering (cheating). In King Lear, Edmund is mad that he's an illegitimate son, because it means he can't inherit the throne.

Definitions of illegitimate
1

adj contrary to or forbidden by law

“an illegitimate seizure of power”
Synonyms:
illicit, outlaw, outlawed, unlawful
illegal
prohibited by law or by official or accepted rules

adj of marriages and offspring; not recognized as lawful

Synonyms:
unauthorised, unauthorized
not endowed with authority
illegal
prohibited by law or by official or accepted rules
adulterine
conceived in adultery
base, baseborn
illegitimate
bastardly, misbegot, misbegotten, spurious
born out of wedlock
fatherless
not having a known or legally responsible father
left-handed
(of marriages) illicit or informal
unlawful, wrongful
having no legally established claim
invalid
having no cogency or legal force
Antonyms:
legitimate
of marriages and offspring; recognized as lawful
authorised, authorized
endowed with authority
legal
established by or founded upon law or official or accepted rules
lawfully-begotten
born in wedlock; enjoying full filial rights
left-handed, morganatic
(of marriages) of a marriage between one of royal or noble birth and one of lower rank; valid but with the understanding that the rank of the inferior remains unchanged and offspring do not succeed to titles or property of the superior
lawful, rightful, true
having a legally established claim
valid
well grounded in logic or truth or having legal force
show more antonyms...

n the illegitimate offspring of unmarried parents

Synonyms:
bastard, by-blow, illegitimate child, love child, whoreson
Type of:
issue, offspring, progeny
the immediate descendants of a person

Sign up, it's free!

Whether you're a student, an educator, or a lifelong learner, Vocabulary.com can put you on the path to systematic vocabulary improvement.