rudiment

noun

ru·​di·​ment ˈrü-də-mənt 

1

: a basic principle or element or a fundamental skill

—usually used in plural

… he had spent several hours educating me on the rudiments of living in the wilderness, alone.

—Ed Caesar

teaching themselves the rudiments of rational government

—G. B. Galanti

2

a

: something unformed or undeveloped : beginning

—usually used in plural

the rudiments of a plan

b(1)

: a body part so deficient in size or structure as to be entirely unable to perform its normal function

(2)

: an organ just beginning to develop : anlage

rudimental

ˌrü-də-ˈmen-tᵊl 

adjective

Synonyms of rudiment

• principles
• elements
• grammar

Examples of rudiment in a Sentence

learned the rudiments of mathematics

Recent Examples on the Web

Thereafter rudiments of order emerged, first under Lieut. — Britannica Editors, Encyclopedia Britannica, 19 Mar. 2026

Very few received even the rudiments of an academic education. — Michael Barnes, Austin American Statesman, 30 July 2025

At the outset the institute will focus just on helping students understand the rudiments of AI. — Steven Zeitchik, HollywoodReporter, 16 Apr. 2026

Endosperm is only found in flowering plants, although a few close relatives like the nonflowering shrubby joint fir, Ephedra, have its rudiments. — Literary Hub, 25 Mar. 2026

Word History

Etymology

Latin rudimentum beginning, from rudis raw, rude

First Known Use

1534, in the meaning defined at sense 1

Kids Definition

rudiment

noun

ru·​di·​ment ˈrüd-ə-mənt 

1

: a basic principle or skill

—usually used in plural

the rudiments of grammar

2

a

: something unformed or undeveloped : beginning

—usually used in plural

b

: a body part so underdeveloped in size or structure that it is unable to perform its normal function

Medical Definition

rudiment

noun

ru·​di·​ment ˈrüd-ə-mənt 

: an incompletely developed organ or part

especially : an organ or part just beginning to develop : anlage