# Dictionary API
> Look up English word definitions with phonetic transcriptions, pronunciation audio, parts of speech and example sentences, plus synonyms and antonyms. Ideal for writing tools, word games, language learning and education apps. Experimental support for 11 more languages.

## Authentication
All requests require your oanor API key in the `x-oanor-key` header. Get one at https://www.oanor.com/developer/keys.

```bash
curl -H "x-oanor-key: oanor_live_…" "https://api.oanor.com/dictionary-api/..."
```

## Pricing
- **Free** (Free) — 4,000 calls/Mo, 2 req/s
- **Basic** ($14/Mo) — 90,000 calls/Mo, 8 req/s
- **Pro** ($39/Mo) — 500,000 calls/Mo, 25 req/s
- **Mega** ($109/Mo) — 2,500,000 calls/Mo, 80 req/s

## Endpoints

### Dictionary

#### `GET /v1/define` — Full word entry

**Parameters:**
- `word` (query, required, string) — Word to define Example: `hello`
- `lang` (query, optional, string) — Language code (en default; hi es fr ja ru de it ko pt-BR ar tr)

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/dictionary-api/v1/define?word=hello"
```

**Response:**
```json
{
    "data": {
        "lang": "en",
        "word": "hello",
        "audio": "https://api.dictionaryapi.dev/media/pronunciations/en/hello-au.mp3",
        "origin": null,
        "license": "CC BY-SA 3.0",
        "meanings": [
            {
                "antonyms": [],
                "synonyms": [
                    "greeting"
                ],
                "definitions": [
                    {
                        "example": null,
                        "antonyms": [],
                        "synonyms": [],
                        "definition": "\"Hello!\" or an equivalent greeting."
                    }
                ],
                "part_of_speech": "noun"
            },
            {
                "antonyms": [],
                "synonyms": [],
                "definitions": [
                    {
                        "example": null,
                        "antonyms": [],
                        "synonyms": [],
                        "definition": "To greet with \"hello\"."
                    }
                ],
                "part_of_speech": "verb"
            },
            {
                "antonyms": [
                    "bye",
                    "goodbye"
                ],
                "synonyms": [],
                "definitions": [
                    {
                        "example": "Hello, everyone.",
                        "antonyms": [],
                        "synonyms": [],
                        "definitio
…(truncated, see openapi.json for full schema)
```

#### `GET /v1/synonyms` — Synonyms + antonyms

**Parameters:**
- `word` (query, required, string) — Word to look up Example: `happy`
- `lang` (query, optional, string) — Language code (en default)

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/dictionary-api/v1/synonyms?word=happy"
```

**Response:**
```json
{
    "data": {
        "lang": "en",
        "word": "happy",
        "antonyms": [
            "inappropriate",
            "inapt",
            "unfelicitous",
            "disenchanted",
            "dissatisfied",
            "blue",
            "depressed",
            "down",
            "miserable",
            "moody",
            "morose",
            "sad",
            "unhappy",
            "unfortunate",
            "unlucky",
            "unpropitious"
        ],
        "synonyms": [
            "happify",
            "cheerful",
            "content",
            "delighted",
            "elated",
            "exultant",
            "glad",
            "joyful",
            "jubilant",
            "merry",
            "orgasmic",
            "fortunate",
            "lucky",
            "propitious"
        ]
    },
    "meta": {
        "timestamp": "2026-05-30T03:24:07.662Z",
        "request_id": "955a7fd8-f4c9-4b53-a1a3-fcefb8ff7cdb"
    },
    "status": "ok",
    "message": "Synonyms retrieved successfully",
    "success": true
}
```


---
Marketplace page: https://www.oanor.com/api/dictionary-api
OpenAPI spec: https://www.oanor.com/api/dictionary-api/openapi.json