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Wiktionary REST API

Free, official Wikimedia endpoint for crowd-sourced multilingual definitions and etymology, straight from Wiktionary.

The Wikimedia REST API exposes Wiktionary's free-content dictionary at /api/rest_v1/page/definition/{word}, returning definitions grouped by language and part of speech with linked terms and usage examples. Because it is the same content powering Wiktionary, coverage spans hundreds of languages, obscure terms, slang, and etymologies that a fixed-vocabulary dictionary API misses. No API key is required; just send a descriptive User-Agent per Wikimedia policy. Strong for multilingual definition lookups and grounding language-related skills.

Free tier

Free (Wikimedia, CC BY-SA content). No key.

Rate limits

No per-key limit, but Wikimedia enforces an aggregate cap (around 200 req/s) and requires a descriptive User-Agent with contact info; heavy unidentified traffic can be blocked.

Auth

No key

Base URL

https://en.wiktionary.org/api/rest_v1

What you'd build with it

  • Multilingual definition lookups beyond fixed-vocabulary dictionaries
  • Etymology and slang/obscure-term enrichment for content pipelines
  • Ground an LLM with crowd-sourced lexical data across many languages
  • Build a translation glossary that cross-references Wiktionary entries

Key endpoints

  • GET/page/definition/{term}Get definitions for a term, grouped by language and part of speech, with usage examples and links.
Members

Members get the runnable recipe

Sign in free to copy the example request, see a sample response, and read the gotchas.

Tags

dictionarydefinitionsetymologymultilingualwikimedia