# Words API

**Canonical:** https://apis.io/providers/words/  
**Website:** https://www.wordsapi.com/  
**APIs profiled:** 9

Words API is a RESTful English-language API that provides definitions, synonyms, antonyms, related words, syllables, pronunciation (IPA), rhymes, frequency, and hierarchical lexical relationships (typeOf, hasTypes, partOf, hasParts, memberOf, similarTo, also, entails, inCategory, inRegion, pertainsTo, etc.) for more than 150,000 English words. Distributed and metered through the RapidAPI marketplace.

## Kin Score — 40.3 / 100 (developing)

Scored 2026-08-20 under rubric 0.12.0. Trend: flat (+0.0 from 40.3).

| Facet | Score |
|---|---|
| Discoverability | 81.5 |
| Contract Quality | 29.2 |
| Governance | 25.0 |
| Contract Governance | 25.0 |
| Operational Transparency | 34.2 |
| Developer Ergonomics | 23.8 |
| Commercial Clarity | 63.2 |
| Access Clarity | 63.2 |

## Agent readiness — 38.3 (agent-ready)

| Dimension | Value |
|---|---|
| Spec Presence | yes |
| Agentic Access | derived |
| Reversibility Documented | na |
| MCP Server | no |
| Auth Clarity | yes |
| Idempotency | na |
| Error Semantics | no |
| OpenAPI Examples | partial |
| Rate Limit Signal | documented |
| Event Surface Described | no |
| Agent Skills | no |
| Well Known Catalog | no |
| Consent Identity | no |
| Agent Card | no |
| Dry Run Mode | na |

## Access

Paid · Self-serve signup — onboarding: self-serve, pricing: paid, trial: no (confidence: high).

## APIs (9)

- **Words API Categories API** — Words API Category, Region, and Domain-Usage Relationships.
- **Words API Definitions API** — Words API Sense-level Definitions Grouped by Part of Speech.
- **Words API Examples API** — Words API Real-world Example Sentences for Each Sense.
- **Words API Frequency API** — Words API Corpus-derived Frequency Statistics (Zipf, perMillion, diversity).
- **Words API Hierarchy API** — Words API Lexical Hierarchies — typeOf, hasTypes, partOf, hasParts, instances.
- **Words API Phonetics API** — Words API Pronunciation (IPA), Syllables, and Rhymes.
- **Words API Search API** — Words API Search and Random Word Discovery Endpoint.
- **Words API Thesaurus API** — Words API Synonyms, Antonyms, and Similar Word Relationships.
- **Words API Word API** — Words API Lookup a Word and Retrieve Its Full Lexical Entry.

## Agentic access (1)

- **Words Agentic Access** — 30 operations

## Security (2)

- **Words Authentication** — apiKey · 1 scheme
- **Words Domain Security** — TLSv1.3 · DNSSEC

## Plans (1)

- **Words Plans Pricing**

## Use cases (8)

- **Dictionary and Thesaurus Applications** — Power dictionary, thesaurus, and "word of the day" applications with definitions, synonyms, and related words.
- **Word Games and Puzzles** — Drive crossword, Scrabble-style, and anagram games with filtered word search, rhymes, and difficulty-tunable random word selection.
- **Writing and Editing Tools** — Build grammar, style, and writing assistants that suggest synonyms, antonyms, and frequency-aware alternatives.
- **Language Learning and Education** — Provide IPA pronunciation, syllable splits, frequency, and example sentences for ESL and vocabulary-building apps.
- **NLP and Text Enrichment** — Enrich downstream NLP pipelines with hypernyms, hyponyms, meronyms, and domain labels for entity expansion.
- **Voice and Speech Applications** — Use IPA pronunciation and syllable data for speech synthesis, ASR vocabulary tuning, and pronunciation coaching.
- **Chatbots and Conversational Agents** — Disambiguate user input by mapping words to their senses, hypernyms, and categories at runtime.
- **Content Generation and Rewriting** — Drive paraphrasing and content-variation engines with synonym, similar-to, and pertains-to relationships.

## Tags

Dictionaries, Linguistics, English, thesaurus, Lexical Data, Public APIs

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Profiled by [API Evangelist](https://apievangelist.com) and published on [APIs.io](https://apis.io/providers/words/). Scores are computed from the provider's own public artifacts under a published rubric.