Dictionary API Documentation

Welcome to the Dictionary API. Build powerful language tools, educational apps, and content platforms with our comprehensive lexical database. Access definitions, synonyms, etymology, and audio pronunciations programmatically.

ℹ️

API v1 is currently in stable release. All endpoints are versioned under /v1/.

Base URL

https://api.dictionary.com/v1

Authentication

Dictionary API uses API keys to authenticate requests. You can view and manage your API keys in the developer dashboard.

Include your API key in the request header:

# Authentication Header
X-API-Key: your_api_key_here

⚠️

Never expose your API keys in client-side code or public repositories. Use environment variables.

Endpoints

GET /lookup/{word}

Retrieves the primary definition, part of speech, phonetics, and usage examples for a given word.

Path Parameters

Parameter	Type	Description
word*	string	The word to look up. Supports Unicode and hyphenated words.

curl -X GET "https://api.dictionary.com/v1/lookup/ephemeral" \\
  -H "X-API-Key: your_api_key_here"

POST /search

Performs advanced lexical searches with filtering, ranking, and cross-language matching.

Request Body

{
  "query": "synonyms for fast",
  "language": "en",
  "limit": 10,
  "filters": {
    "pos": ["adjective", "adverb"],
    "exclude": ["slang"]
  }
}

GET /synonyms/{word}

Returns a ranked list of synonyms, antonyms, and related terms based on contextual usage.

Supports optional query parameters for filtering by part of speech or semantic domain.

Error Handling

The Dictionary API uses standard HTTP status codes to indicate success or failure. Error responses include a JSON body with details:

Code	Meaning	Description
400	Bad Request	Invalid parameters or malformed JSON.
401	Unauthorized	Missing or invalid API key.
404	Not Found	Word not found in the database.
429	Too Many Requests	Rate limit exceeded.
500	Server Error	Internal server error. Retry after 2s.

{
  "error": {
    "code": 404,
    "message": "Word not found",
    "details": "The term 'xyzabc' does not exist in our lexicon."
  }
}

Rate Limits

API requests are rate-limited based on your subscription tier. Limits are applied per API key per minute.

Free Tier: 60 requests/minute
Pro Tier: 600 requests/minute
Enterprise: Custom limits (10,000+/min)

Rate limit headers are included in every response:

X-RateLimit-Limit: 600
X-RateLimit-Remaining: 598
X-RateLimit-Reset: 1678901234

SDKs & Tools

Official SDKs are available for popular languages to simplify integration:

Python: pip install dictionary-api
JavaScript/Node.js: npm install @dictionary/api
Ruby: gem install dictionary_api
Go: go get github.com/dictionary/go-sdk

Community-maintained packages and Postman collections are available on our GitHub organization.