Synonyms
Synonyms, thesaurus and antonyms information for any given word
- Authentication
- API Key
- HTTPS
- Yes
- CORS
- Unknown
- Category
- Dictionaries
- Data source
- public-apis + marcelscruz
- Documentation / URL
- https://www.synonyms.com/synonyms_api.php
Overview
Synonyms.com provides synonym and antonym lookups — key-based.
⚠️ Status (verified 2026-08): the endpoint returned HTTP 403 Forbidden (nginx) — likely datacenter-IP blocking or an auth gate. Try from a residential/browser context and with a valid key.
What it provides
curl "https://www.synonyms.com/synonyms.php?term=happy&format=json" \
-H "Authorization: Bearer YOUR_KEY"Notes
- Synonyms/antonyms for terms.
- Key-based per the API docs.
FAQ
Is Synonyms free? Key-based with a free tier per the docs.
Why 403? Our 2026-08 test hit 403 (verified) — likely IP blocking; verify from your network.
What does it do? Synonym lookups.
More in Dictionaries
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|---|---|---|---|---|
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| Collins Bilingual Dictionary and Thesaurus Data | API Key | Yes | Unknown | ↗ |
| Free Dictionary Definitions, phonetics, pronounciations, parts of speech, examples, synonyms | No auth | Yes | Unknown | ↗ |
| Indonesia Dictionary Indonesia dictionary many words | No auth | Yes | Unknown | ↗ |