Frequently asked questions
How the dictionary works, where the definitions come from, and what you can do with them.
What is whatisa.net?
A free online English dictionary with short definitions of 84,879 words. Type a word in the box on the homepage or go to whatisa.net/?word.
How do I look up a word?
Type it in the search box and press Enter, or add it to the address after a question mark: whatisa.net/?serendipity, whatisa.net/?volcano, whatisa.net/?algorithm. Capital letters and a leading “a”, “an” or “the” are ignored, so ?The%20Volcano finds “volcano”.
Can I look up phrases?
Only single words, including hyphenated words (such as a-frame) and words with apostrophes. The dictionary does not contain multi-word phrases such as “machine learning”.
Why is a word missing?
The list has 84,879 entries, which covers common vocabulary and many technical terms but not every word. Inflected forms (plurals, past tenses) are usually not listed separately, so try the base form: “volcano” instead of “volcanoes”. If a word is missing, the “Did you mean?” box shows similar entries, and the A–Z index lists everything that is available.
Where do the definitions come from?
From English Wiktionary. The definitions are condensed and shared under the CC BY-SA 4.0 licence. Every word page links to its original Wiktionary entry.
Some definitions look cut off or odd. Why?
The text was extracted automatically from Wiktionary, and words that came from templates in the source were sometimes dropped, leaving gaps such as “a tree of the genus .”. For some words only certain senses survived. The linked Wiktionary entry always has the complete, current definition.
How do I share or bookmark a definition?
Copy the address from your browser. Each word has a permanent URL, for example https://whatisa.net/?glacier.
Can I reuse the definitions?
Yes, under the terms of CC BY-SA 4.0: credit Wiktionary (and link to the entry or to the licence), and share your adapted text under the same licence. See the terms of use.
Is it free? Do I need an account?
It is free and there are no accounts or sign-ups. There are no ads.
Do you track my searches?
The site uses Google Analytics, which records the pages you visit, and because each word is a page, the words you look up appear in those statistics. No account or personal profile is created on whatisa.net. Details are in the privacy policy and cookie policy.
Is there an API?
No. The dictionary files are plain JSON split by the first two letters of each word (for example /assets/vo.json), but there is no official API. For programmatic access to Wiktionary data, the Wikimedia projects provide their own downloads and APIs.
How do I report a mistake?
Email [email protected] with the word and what is wrong. Because the definitions come from Wiktionary, the most lasting fix is to correct the Wiktionary entry itself.