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.

open word class

/ˈoʊpən wɜːrd klæs/
phrase★Intermediate— grammatical categories that can function as multiple parts of speech
technical

A grammatical category of words that can function as multiple parts of speech and can be freely added to a language (e.g., verbs, nouns, adjectives)

In English, words like 'run' can be both verbs and nouns, making them part of the open word class.

This flexibility is a key feature of open word classes.

💡

Contrast with closed word classes (e.g., pronouns, prepositions), which have fixed members.

Collocations

closed word classgrammatical categories with fixed members (e.g., pronouns, prepositions)

Synonyms

flexible word classproductive word class

Antonyms

closed word class

Related Phrases

closed word classphrase
grammatical categories with fixed members

💡Pro Tip

Key Examples

Common open word classes include verbs, nouns, adjectives, and adverbs.

⚡Gold Rule

Flexibility

Open word classes can be freely added to a language, unlike closed word classes.

📖Word Origin

Derived from the linguistic distinction between words that can be freely added to a language (open) and those with fixed membership (closed).

📝Usage Notes

Open word classes are often contrasted with closed word classes, which have a limited set of members (e.g., pronouns, prepositions).

Word Breakdown

open
able to be freely added to a language
adjective
+
word class
a grammatical category of words
noun phrase
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.