a. Being against established or accepted rules and standards: an illegitimate means of winning a debate.
b. Being against the law; illegal: an illegitimate contract.
c. Not valid or defensible: Their reasons for missing school are illegitimate.
d. Incorrectly deduced; illogical: an illegitimate conclusion.
e. Biology Unacceptable as a scientific name because of not conforming to the international rules of nomenclature.
2. Offensive Born to parents not married to each other.
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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