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 Boys from Syracuse), this very ’90s version of the classic fairytale features eye-popping costumes and sets, adorably rudimentary VFX, and a truly unbelievable cast (Brandy! —Vogue, 15 Feb. 2025

First signs of rudimentary Valentine notes began appearing much later, in the 1500s, according to Britannica. —Eric Lagatta, USA TODAY, 14 Feb. 2025

Austin Barnes, one of the few Dodgers who had faced Sasaki before during the World Baseball Classic, squatted behind the plate as Sasaki mixed his two main pitches into a rudimentary procedure on a chilly February morning in Arizona. —Fabian Ardaya, The Athletic, 13 Feb. 2025

Here the underlying image is a sweeping, but somewhat rudimentary, aerial view of the Christopher Columbus statue at the southwest corner of New York’s Central Park, where it is ringed concentrically by a pedestrian plaza, a traffic circle, and two high-rise towers. —Mara Hoberman, Artforum, 1 Feb. 2025

Word History

Etymology

see rudiment

First Known Use

1619, in the meaning defined at sense 1

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