Find the right word, every time.
Synonyms and antonyms for any word, in a single API call — perfect for writing tools, vocabulary apps, and content generation.
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A curated English word dataset, ready for production.
Thesaurus returns both synonyms and antonyms for a word in a single request. Lookups are case-insensitive and served from an in-memory dataset for fast, low-latency responses.
{
"word": "happy",
"synonyms": ["joyful", "cheerful", "content"],
"antonyms": ["sad", "unhappy", "miserable"]
}
One GET request. No body, no parsing.
Pass the word in the URL path. Your API key in the header. No SDK, no setup, no request body. The response is flat JSON — read it directly without unwrapping nested structures.
GET /v1/text/thesaurus/happy
Host: requiems.xyz
requiems-api-key: YOUR_API_KEY
Built for writing and content tools.
Thesaurus fits anywhere vocabulary matters — writing assistants, education, and content generation alike.
Suggest alternatives while users write
Offer synonym suggestions inline as users type, helping them avoid repeating the same word across a document.
Power vocabulary-building apps
Build flashcard or word-of-the-day apps that pair each word with its synonyms and antonyms for deeper learning.
Generate word game content
Use synonym and antonym pairs to build word-guessing games, crosswords, or vocabulary quizzes without maintaining your own dataset.
Support educational platforms
Give students instant synonym and antonym lookups inside reading or writing exercises, without leaving the platform.
Diversify content and improve SEO
Suggest synonyms for overused keywords to avoid repetition and improve readability in generated or edited content.
Add vocabulary depth to chatbots
Let conversational agents rephrase responses with synonyms to sound more natural and avoid repetitive phrasing.
Use together with complementary APIs.
Thesaurus works even better when paired with other Requiems APIs.
Correct spelling first, then suggest richer word choices — a complete writing-assistance pipeline in two calls.
Analyze the tone of a text, then suggest synonyms to soften or strengthen specific words based on the detected sentiment.
Suggest clean synonym alternatives for flagged words instead of just censoring them.
Frequently Asked Questions
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Give your content the right words.
One API key. Thesaurus, spell check, sentiment analysis, and 50+ other APIs for building smarter writing tools.