unsuccessful
Americanadjective
adjective
Other Word Forms
Derived Forms
Etymology
Origin of unsuccessful
First recorded in 1610–20; un- 1 + successful
Explanation
When something is unsuccessful, it means it didn’t quite work out as planned, like trying to bake a towering, multilayered cake and ending up with a pancake instead. The word unsuccessful comes from the Latin roots un- meaning "not" and successus, meaning "a good outcome." It describes an attempt that doesn’t achieve its intended result. For example, an unsuccessful attempt at gardening will result in wilted plants rather than beautiful blooms. Although being unsuccessful can be frustrating, it’s also a valuable part of learning and growing. Many great inventors and artists faced unsuccessful attempts before finally succeeding.
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.
The development commission has recommended reviving the Hood County data center moratorium proposal, but those efforts have so far been unsuccessful in being added to the commissioners’ agenda.
From Salon • Jun. 6, 2026
His missions included rescuing several Naval aviators and one unsuccessful attempt to rescue a Navy deckhand who fell overboard in the middle of the night.
From The Wall Street Journal • Jun. 5, 2026
For several days, the driver and passengers made repeated attempts to repair the vehicle, but their efforts ultimately proved unsuccessful.
From BBC • Jun. 5, 2026
He sought "revenge" for the court defeat and a series of unsuccessful criminal complaints, and wanted to "continue to attract public and media attention", the prosecutor argued.
From Barron's • Jun. 4, 2026
Apparently they were not discouraged by the earlier unsuccessful attempt to remove my name from the roll because of my conviction in the Defiance Campaign.
From "Long Walk to Freedom" by Nelson Mandela
![]()
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.