Vocapedia
Log inTry for Free
Log in

Looking up...

Words

  • Words of the Year
  • Recent Lookups
  • My Dictionary

Languages

  • English
  • Vietnamese
  • Japanese
  • Chinese
  • Spanish
  • French
  • Korean
  • German

Features

  • Words of the Year
  • My Collections List
  • Reviews
  • Learning Resources
  • Community Collections

Learn

  • How It Works
  • Study Guides
  • Language Tips
  • FAQ
  • Getting Started
  • For Individuals
  • For Teachers

Community

  • Forum
  • Blog
  • Help Center
  • Partnerships

About

  • About Vocapedia
  • Contact Us
  • Feedback

Legal

  • Terms of Use
  • Privacy Policy
  • Cookie Policy
  • Accessibility
  • GDPR Compliance
© 2026 Vocapedia. All rights reserved.

warn

/wɔːrn/
verb★Beginner— to alert someone to a danger or problem
general

to inform someone of a potential danger or problem so they can take action

The doctor warned her about the side effects of the medication.

The doctor informed her about possible negative effects of the medication.

💡

Often used to encourage caution or preparation.

⚖️Law
formal

to give a formal notice or caution, often in a legal or official context

The company was warned about violating safety regulations.

The company received an official notice about breaking safety rules.

💡

In legal contexts, a warning may be a formal notice before legal action.

Collocations

warn someone aboutto inform someone of a specific danger or problemwarn ofto indicate a potential danger or issue

Synonyms

alertcautionnotifyadmonish

Antonyms

ignoreoverlookencourage

Related Phrases

a word of warningphrase
a piece of advice or caution

💡Pro Tip

Formal vs. Informal Use

In formal contexts, 'warn' can imply legal consequences, while in everyday speech, it's often just a friendly caution.

⚡Gold Rule

Legal Implications

In legal or professional settings, a warning may require a documented response.

📖Word Origin

Old English *warnian, from Proto-Germanic *warnōjanan, meaning 'to take heed, guard against'

📝Usage Notes

Can be used in both formal and informal contexts, but formal warnings often carry legal implications.

Word Breakdown

warn
to alert or caution
root
English Dictionary

Learning Progress

Track your learning journey!

• Save words to build your vocabulary

• Monitor your daily streak

• Get personalized review reminders

• See words learned statistics

Log in to access advanced features and track your progress!

Go to Dashboard →

Recent Lookups

The most recent words being looked up. Stay up to date with what language learners are exploring.