rudimentary

adjective

ru·​di·​men·​ta·​ry ˌrü-də-ˈmen-tə-rē 

-ˈmen-trē

1

: consisting in first principles : fundamental

had only a rudimentary formal education

—D. J. Boorstin

2

: of a primitive kind

the equipment of these past empire-builders was rudimentary

—A. J. Toynbee

3

: very imperfectly developed or represented only by a vestige

the rudimentary tail of a hyrax

rudimentarily

ˌrü-də-ˌmen-ˈter-ə-lē 

-ˈmen-trə-lē

adverb

rudimentariness

ˌrü-də-ˈmen-tə-rē-nəs 

-ˈmen-trē-

noun

Synonyms

• crude
• low
• primitive
• rude

Examples of rudimentary in a Sentence

Because now, every schlemiel with a pair of mirrored sunglasses and a rudimentary grasp of the rules of poker thinks he can play cards with the pros. —A. J. Jacobs, New York Times Book Review, 8 May 2005

Despite the rudimentary nature of its instruments—an octant, a chronometer and a level—the Lewis and Clark Expedition was a triumph for science and natural history. —Daniel J. Boorstin, U.S. News & World Report, 11 July 1994

A few were hopeless imbeciles, unable to comprehend more than the rudimentary requirements of filling their bellies when food was placed before them … —Edgar Rice Burroughs, The Monster Men, 1929

This class requires a rudimentary knowledge of human anatomy.

When baseball was in its rudimentary stages, different teams played by different rules.

Some insects have only rudimentary wings.

Recent Examples on the Web

The adjustable-length stirrups will suit a wide range of riders, holding onto a rudimentary handlebar and sitting on a floating seat unit long enough to take a passenger, and capable of moving independently from the robot's ... butt joints. —New Atlas, 6 Apr. 2025

Added to the chaos is the underlying rudimentary calculation of tariff levels that have produced wildly uneven and irrational effects on trading partners with no readily discernible policy value. —Jerrold Lundquist, Forbes.com, 5 Apr. 2025

But one assistant coach is struck by a more rudimentary pattern these days. —Bennett Durando, Denver Post, 31 Mar. 2025

There are secure lines of communication to do this, and anybody with just a rudimentary understanding of how national security works knows this. —Caitlin Yilek, CBS News, 25 Mar. 2025

Word History

Etymology

see rudiment

First Known Use

1619, in the meaning defined at sense 1

Rhymes for rudimentary

• alimentary
• complimentary
• documentary
• parliamentary
• sedimentary
• supplementary
• testamentary
• integumentary
• uncomplimentary
• unparliamentary
• interparliamentary
• metasedimentary

Kids Definition

rudimentary

adjective

ru·​di·​men·​ta·​ry ˌrüd-ə-ˈment-ə-rē 

-ˈmen-trē

1

: elementary sense 1, fundamental

2

: very imperfectly developed or represented only by a small part compared to the fully developed form

a rudimentary tail

Medical Definition

rudimentary

adjective

ru·​di·​men·​ta·​ry ˌrüd-ə-ˈment-ə-rē, -ˈmen-trē 

: very imperfectly developed or represented only by a vestige