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Synonyms

undisciplined

British  
/ ʌnˈdɪsɪˌplɪnd /

adjective

  1. not exhibiting self-control or good behaviour

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

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.

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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.

“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