Dictionary API

Access 15M+ words, definitions, synonyms, and translations across 100+ languages via a simple, high-performance RESTful API.

Authentication Browse Endpoints Install SDK

cURL

curl https://api.dictionary.com/v1/words/ephemeral \
  -H "Authorization: Bearer <YOUR_API_KEY>"

50ms

Avg. Latency

99.99%

Uptime SLA

2B+

Requests/Day

Authentication

All API requests require authentication via Bearer token. Include your API key in the Authorization header.

Header

Authorization: Bearer sk_live_8f9a2b3c4d5e6f7g8h9i0j

Never expose your secret keys in client-side code. Use environment variables or backend proxies.

API Endpoints

GET /v1/words/{word} Retrieve definitions & metadata ▼

Fetches comprehensive data for a single word including definitions, pronunciation, etymology, and usage examples.

Path Parameters

Name	Type	Required	Description
`word`	string	Yes	The word to look up

Response

{
  "word": "ephemeral",
  "phonetic": "/əˈfem.ər.əl/",
  "definitions": [
    {
      "part_of_speech": "adjective",
      "definition": "Lasting for a very short time",
      "example": "The ephemeral beauty of cherry blossoms."
    }
  ],
  "source": "dictionary.com"
}
                            

POST /v1/definitions Get AI-powered definition ▼

Uses our language model to generate contextual definitions, even for slang, neologisms, or technical jargon.

Request Body

Name	Type	Required	Description
`text`	string	Yes	The word or phrase
`language`	string	No	ISO 639-1 code (default: en)
`level`	string	No	`simple` or `advanced`

Response

{
  "text": "algorithm",
  "definition": "A step-by-step procedure for solving a problem or accomplishing a task, especially by a computer.",
  "confidence": 0.98,
  "context_tags": ["computing", "mathematics"]
}
                            

GET /v1/synonyms?word= Find related words & alternatives ▼

Returns synonyms, antonyms, and related terms ranked by semantic similarity.

Query Parameters

Name	Type	Required	Description
`word`	string	Yes	Target word
`limit`	integer	No	Max results (default: 10)

Response

{
  "word": "happy",
  "synonyms": ["joyful", "cheerful", "content"],
  "antonyms": ["sad", "miserable"],
  "related": ["delight", "pleasure"]
}
                            

POST /v1/translate Context-aware translation ▼

Translates words or phrases with awareness of idiomatic usage and regional variations.

Request Body

Name	Type	Required	Description
`text`	string	Yes	Text to translate
`target_lang`	string	Yes	Target ISO 639-1 code
`source_lang`	string	No	Auto-detected if omitted

Response

{
  "translated_text": "Bonjour le monde",
  "source_lang": "en",
  "target_lang": "fr",
  "confidence": 0.99
}
                            

Rate Limits

API requests are throttled based on your plan tier. Headers indicate your current usage.

Header	Description
`X-RateLimit-Limit`	Max requests per window
`X-RateLimit-Remaining`	Requests left in current window
`X-RateLimit-Reset`	Unix timestamp when quota resets

Exceeding limits returns 429 Too Many Requests. Implement exponential backoff for resilience.

Error Handling

The API uses standard HTTP status codes and returns detailed error payloads.

Code	Meaning	Resolution
`400`	Bad Request	Check parameters and payload format
`401`	Unauthorized	Verify API key & expiration
`403`	Forbidden	Insufficient permissions for endpoint
`404`	Not Found	Word not in database or invalid path
`429`	Rate Limited	Wait for reset time, retry with backoff
`500`	Server Error	Internal issue, try again later or contact support

Official SDKs

Get started faster with our type-safe, auto-generated client libraries.

Python

Asyncio-ready with full type hints.

pip install dictionary-api

Node.js

Promises & streams supported.

npm install @dictionary/sdk

Ruby

Optimized for Rails & CLI apps.

gem install dictionary_api

Go

High performance, thread-safe.

go get github.com/dictionary/api-go