Definition of illegitimate
1 : not recognized as lawful offspring specifically : born of parents not married to each other
2a : not sanctioned by law : illegal
b : not authorized by good usage
c of a taxon : published but not in accordance with the rules of the relevant international code
3 : not rightly deduced or inferred : illogical
4 : departing from the regular : erratic
Keep scrolling for more
Keep scrolling for more
Keep scrolling for more
Keep scrolling for more
Test Your Vocabulary
Words of Snow and Ice Quiz
- Which of the following refers to thin, bending ice, or to the act of running over such ice?

Test your knowledge - and maybe learn something along the way.
TAKE THE QUIZ
Anagram puzzles meet word search.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridgedWords at Play
Ask the Editors
Word Games
Words of Snow and Ice Quiz
A selection of words from the chillier parts of t...
Take the quizName that Thing: Toys and Games Edition
It's all fun and games until someone beats your h...
Take the quizTrue or False?
Test your knowledge - and maybe learn something a...
Take the quizSCRABBLE® Sprint
SCRABBLE® fans, sharpen your skills!
Play the game
Share illegitimate
Time Traveler for illegitimate
The first known use of illegitimate was in 1536
See more words from the same year