- 1undermine something to make something, especially someone's confidence or authority, gradually weaker or less effective Our confidence in the team has been seriously undermined by their recent defeats. This crisis has undermined his position. Recent changes have undermined teachers' morale.
Take your English to the next level
The Oxford Learner’s Thesaurus explains the difference between groups of similar words. Try it for free as part of the Oxford Advanced Learner’s Dictionary app
- 2undermine something to make something weaker at the base, for example by digging under it
undermine
verbNAmE//ˈʌndərˌmaɪn//, NAmE//ˌʌndərˈmaɪn//
Verb Forms present simple I / you / we / they undermine he / she / it undermines
past simple undermined
-ing form undermining
Check pronunciation: undermine