undisciplined
Britishadjective
Explanation
Undisciplined means uncontrolled or disorderly. An undisciplined bunch of dogs is nearly impossible to walk down the sidewalk together: they all want to run in different directions, chase squirrels, and bark wildly. When you take the word disciplined, "showing control or order," and add un-, or "not," to it, you get undisciplined. This is a great way to describe an out-of-control classroom, an athlete whose explosive anger gets her kicked off the field, or someone who can't manage his own money well, spending an entire paycheck all in one place.
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.
“His mind was, from what I could see, largely undisciplined, which is how he could make these connections so unexpectedly and usefully, but not always usefully,” Crocker said.
From The Wall Street Journal • Mar. 6, 2026
While much of this work may look wild or undisciplined — it certainly did to adherents of the International Style — it in fact required extraordinary craft and skill.
From Los Angeles Times • Aug. 6, 2025
They are slow, out of shape, undisciplined, and appear very poorly coached.
From Los Angeles Times • Sep. 21, 2024
His speeches and press conferences are surreal windows into his undisciplined, puerile mind.
From Salon • Sep. 6, 2024
These young men were untrained and undisciplined and became involved in activities that were unbecoming to a liberation struggle.
From "Long Walk to Freedom" by Nelson Mandela
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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.