English Dictionary API
FreemiumEnglish definitions, synonyms, antonyms, rhymes, 'words that mean…' and autocomplete — fast and fully offline.
Documentation
English definitions, synonyms, antonyms, rhymes, 'words that mean…' and autocomplete.
What you get
- Definitions grouped by part of speech, with example sentences, synonyms and antonyms
- Related words — broader and narrower terms, parts and wholes
- Rhymes (perfect and near) for poetry and lyrics apps
- Reverse dictionary — find words from a meaning
- Autocomplete for search boxes
Great for word games, writing assistants, e-learning, crosswords and language-learning apps.
Quick start
Subscribe to a plan (the Basic plan is free), then call the API at https://english-dictionary.p.apihiver.com with your key in the X-API-Key header:
curl "https://english-dictionary.p.apihiver.com/v1/define/happy" \
-H "X-API-Key: YOUR_API_KEY"Endpoints
| Method | Path | What it does |
|---|---|---|
GET | /v1/define/{word} | Definitions, examples, synonyms and antonyms of an English word |
GET | /v1/related/{word} | Broader (hypernym) and narrower (hyponym) words — e.g. dog → canine / puppy |
GET | /v1/rhymes/{word} | Words that rhyme (perfect and near rhymes) |
GET | /v1/similar | Words with a similar meaning to a word or phrase (reverse dictionary) |
GET | /v1/autocomplete | Spelling-tolerant word suggestions as the user types |
Open the Endpoints tab to see every parameter, example request and example response, and to try the API live.
Errors
Every error is JSON with the same shape:
{"error": {"code": "INVALID_INPUT", "message": "Send a single English word or short phrase (letters, spaces, hyphens)."}}| HTTP | Code | Meaning |
|---|---|---|
| 400 | INVALID_INPUT | A parameter is missing or has the wrong format — the message says which |
| 401 | UNAUTHORIZED | Missing or invalid X-API-Key |
| 404 | NOT_FOUND | Nothing matched the code, id or name you sent |
| 429 | — | Plan quota or rate limit reached (see the X-RateLimit-* headers) |
| 502 / 503 / 504 | — | A data source or the API server is temporarily unavailable — retry after a few seconds |
Data & privacy
Data comes from Princeton WordNet (offline) and the Datamuse word API.
English Dictionary API FAQ
- Is the English Dictionary API free?
- Yes. The Basic plan is free and includes 500 requests per month — no card needed. Paid plans start at ₹299 per month for 10,000 requests.
- How much does the English Dictionary API cost?
- Basic: free for 500 requests; Pro: ₹299/month for 10,000 requests; Ultra: ₹999/month for 50,000 requests; Mega: ₹2,499/month for 2,00,000 requests. Billing is monthly and you can cancel any time.
- How do I use the English Dictionary API?
- Subscribe to a plan on APIHiver, create an API key in the Console, then send requests to https://english-dictionary.p.apihiver.com with your key in the X-API-Key header. You can also try every endpoint in the browser playground first.
- What endpoints does the English Dictionary API have?
- It has 5 endpoints: Definitions, examples, synonyms and antonyms of an English word (GET /v1/define/{word}); Broader (hypernym) and narrower (hyponym) words — e.g. dog → canine / puppy (GET /v1/related/{word}); Words that rhyme (perfect and near rhymes) (GET /v1/rhymes/{word}); Words with a similar meaning to a word or phrase (reverse dictionary) (GET /v1/similar); Spelling-tolerant word suggestions as the user types (GET /v1/autocomplete).
- What are the English Dictionary API rate limits?
- Basic: 2 requests per second; Pro: 5 requests per second; Ultra: 10 requests per second; Mega: 20 requests per second. Monthly quotas depend on the plan; every response includes X-RateLimit headers showing what's left.
- Can I use one API key for the English Dictionary API and other APIs?
- Yes. One APIHiver key works for every API you subscribe to, so you don't need a separate account or key per provider.
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Endpoints
5 endpoints — full list is in the sidebar on larger screens.