undermine
Americanverb (used with object)
-
to injure or destroy by insidious activity or imperceptible stages, sometimes tending toward a sudden dramatic effect.
-
to attack by indirect, secret, or underhand means; attempt to subvert by stealth.
-
to make an excavation under; dig or tunnel beneath, as a military stronghold.
-
to weaken or cause to collapse by removing underlying support, as by digging away or eroding the foundation.
verb
-
(of the sea, wind, etc) to wear away the bottom or base of (land, cliffs, etc)
-
to weaken gradually or insidiously
their insults undermined her confidence
-
to tunnel or dig beneath
Other Word Forms
- underminer noun
Etymology
Origin of undermine
First recorded in 1300–50; Middle English underminen; under-, mine 2
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.
"Don't let AI technology undermine your willingness to trust anything you see and hear," said Hannah Covington, senior director of education content at the nonprofit News Literacy Project.
From Barron's • Apr. 2, 2026
“This underscores how conflicting geopolitical interests in one theater of conflict may undermine cooperation in another,” said Anne Frühauf, an analyst at consulting firm Teneo.
From The Wall Street Journal • Apr. 1, 2026
He went on to say the lights could become "a source of annoyance to people" and "harmful to wildlife", and added that he felt they could "undermine enjoyment of the countryside or the night sky".
From BBC • Mar. 28, 2026
“The risk is that constant flip-flopping and headline fatigue is starting to seriously undermine the efficacy of the ‘Trump put,’” Barclays analysts said in an equity research note Friday.
From MarketWatch • Mar. 27, 2026
“I have a surprise for you,” he said before she could kiss him and undermine his good intentions.
From "Strange the Dreamer" by Laini Taylor
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.
