rudimentary
Americanadjective
-
pertaining to rudiments or first principles; elementary.
a rudimentary knowledge of geometry.
- Synonyms:
- initial, fundamental
- Antonyms:
- advanced
-
Biology. of the nature of a rudiment; undeveloped or vestigial.
- Synonyms:
- embryonic
- Antonyms:
- mature
-
in an early, imperfect stage or form.
How can we improve upon this admittedly rudimentary theory?
adjective
-
basic; fundamental; not elaborated or perfected
-
incompletely developed; vestigial
rudimentary leaves
Synonym Usage
See elementary.
Other Word Forms
Etymology
Origin of rudimentary
Explanation
Rudimentary means basic, or at a very early stage. The test should be easy: it requires only a rudimentary understanding of the materials. The word rude means simple or offensive — and people with only rudimentary understanding of good manners might not know how that belching is rude. If you remember that the word rude is the foundation of rudimentary, you'll have a rudimentary understanding of the word.
Vocabulary lists containing rudimentary
Essential Academic Vocabulary for High School Students, List 4
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Job prospects and earnings for people who lack rudimentary language and math skills can be severely limited.
From The Wall Street Journal ● Jun. 16, 2026
From its origins as a rudimentary headcount under colonial rule, India's census questionnaire has steadily expanded in scope, mirroring the state's changing priorities.
From BBC ● Mar. 31, 2026
The other was being recruited by Arnold Beckman, a Caltech alum, a renowned inventor of scientific instruments, and scientific advisor to L.A.’s rudimentary air pollution control operation.
From Los Angeles Times ● Mar. 26, 2026
Anyone with even rudimentary knowledge of recent history would have known this was likely.
From Salon ● Mar. 15, 2026
The night remained calm and still, but Matthias and Constance stayed alert, both knowing if they failed to observe this rudimentary law of nature, the penalty could be fatal.
From "Redwall" by Brian Jacques
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.