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English vocabulary data from the edge

English vocabulary for your app. One JSON API.

Add definitions, IPA pronunciation, etymology and available translations to your app with one API. Start with stored, AI-assisted English vocabulary records and test the words your users actually need.

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162K+ stored English headwords. Translation coverage spans 47 language codes and varies by word. Records are AI-assisted and have not been independently human verified. Free tier: 10,000 calls/day. Evaluate stored records with batch lookup.
162,253
Words
601,143
Translations
45,916
Assessment Items
30,526
Graph Links

Explore the data with one API key

Word Orb

162K+ English headwords · optional translations across 47 language codes

Stored definitions, IPA, etymology and available translations. Inspect coverage and accuracy for your application before production use.

  • Available fields include definition, IPA, etymology, translations and audio URL
  • Age-adapted variants are available for a limited subset of words
  • Batch lookup up to 50 words per request

Lesson Orb

Daily lesson infrastructure · 19 lesson languages · 4 tracks · 10 supported archetypes

Structured lesson context around the shared daily experience: five phases, four tracks, and the pedagogical layer behind Kelly.

  • 5 lesson phases: hook, story, wonder, action, wisdom
  • 4 tracks: learn, grow, teach, trivia
  • Explore available lesson and vocabulary connections through the graph

Assessment Layer

45,916 assessment items · 6 question types

Assessment objects aligned to vocabulary and lesson structure, so teams can test exactly what they teach.

  • Review question content and lesson alignment for your application
  • Random, by-day, and batch modes with difficulty filtering
  • Each question includes the answer and an explanation

Knowledge Graph

30,526 connections · words ↔ lessons ↔ assessments

The graph is the glue. It lets teams trace a word into the lessons that teach it and the assessment items that verify it.

  • Find stored lesson connections where available for a word
  • Inspect the vocabulary linked to a lesson
  • Build complete teach-then-test cycles from three API calls

Three examples, inspectable JSON

curl JavaScript Python
# 1. Look up the word curl https://wordorb.ai/api/word/courage \ -H "Authorization: Bearer wo_YOUR_KEY" # 2. Get a structured lesson curl "https://wordorb.ai/api/lesson?day=47&track=learn" \ -H "Authorization: Bearer wo_YOUR_KEY" # 3. Assess comprehension curl "https://wordorb.ai/api/quiz?day=47&track=learn" \ -H "Authorization: Bearer wo_YOUR_KEY"
const API = 'https://wordorb.ai/api'; const h = { 'Authorization': 'Bearer wo_YOUR_KEY' }; // 1. Look up the word const word = await fetch(`${API}/word/courage`, {headers: h}) .then(r => r.json()); // 2. Get a structured lesson const lesson = await fetch(`${API}/lesson?day=47&track=learn`, {headers: h}) .then(r => r.json()); // 3. Assess comprehension const quiz = await fetch(`${API}/quiz?day=47&track=learn`, {headers: h}) .then(r => r.json());
import requests API = "https://wordorb.ai/api" h = {"Authorization": "Bearer wo_YOUR_KEY"} # 1. Look up the word word = requests.get(f"{API}/word/courage", headers=h).json() # 2. Get a structured lesson lesson = requests.get(f"{API}/lesson?day=47&track=learn", headers=h).json() # 3. Assess comprehension quiz = requests.get(f"{API}/quiz?day=47&track=learn", headers=h).json()

Evaluate stored vocabulary

Inspect actual responses, measure coverage, and decide whether the data fits your product.

Stored records

Batch lookup reads existing records without generating missing words. Store the responses used in your evaluation; the underlying data can be updated.

Inspectable

Review the JSON directly. Definitions and translations are AI-assisted; independent human review and record-level source attribution are not provided.

Hosted API

Served on Cloudflare Workers with stored records in D1 and edge caching. Measure response time from your own application and region.

Connect your app or agent

Use REST from your app, or configure the remote MCP endpoint in a compatible client. Check your client’s connection requirements.

MCP Config
{"mcpServers":{"word-orb":{"url":"https://wordorb.ai/mcp"}}}

AI Agents

Give your agent access to stored lexical records through MCP. Evaluate accuracy and coverage before relying on the results.

Learning Products

365 days of structured curriculum with vocabulary, assessments, and knowledge graph links. Education guide →

Robotics

Explore available pronunciation audio, age variants and structured JSON. Coverage varies by word. Robotics guide →

Start building in 60 seconds

Free tier: 10,000 API calls per day. No credit card. Test representative words and review the responses before choosing a paid plan.

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npm install wordorb pip install wordorb

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