The XF English Dictionary API provides definitions, linguistic analysis, and related words for more than one million words and phrases (including many proper nouns, for example names of cities, famous people etc). Get examples, synonyms, antonyms, pronunciations (including audio) and learner-friendly word frequency data with this API.
From the provider:
"The XF English Dictionary contains over one million words and phrases. By default, the API query returns word/phrase definitions,
usage examples, word forms, synonyms, antonyms, pronunciations (both textual and audio), and learner-friendly word frequency
data. You can use a number of parameters to select what exactly will be included in the response. Both request and response are JSON structures.
You can submit either a word or arbitrary text where the target word is selected. The API breaks the text into sentences,
applies linguistic analysis to the sentence where the target word is located, identifies possible root forms of the target word, and returns a list of words, most relevant results at top of the list. For example, if you submit sentence
'RapidAPI is without a doubt the best API marketplace.' where 'doubt' is the target word, linguistic analysis helps us figure out that, in this context, 'doubt' is most likely a noun. Consequently, NOUN 'doubt' is added to the word list before VERB.
The accuracy of linguistic analysis depends on context, but it is, on average, over 90%.
Note that the response also contains phrases that the target word may be part of.
The XF English Dictionary often adds certain related/useful words to the response. These words may help language learners to better
grasp the meaning of the target word. For instance, if you submit a sentence like
'RapidAPI is undoubtedly the best API marketplace.'
the API will (by default) return definitions for both 'undoubtedly' and 'doubt'. Related words can be excluded from
response by setting parameter ’relatedWords’ to ’false’."
If a proper noun is not found in the dictionary, the API may return link(s) to Wikipedia articles.
The dictionary data comes from multiple sources, mainly from Wiktionary and WordNet.