Word Highlighter is a free and open-source Chrome extension developed by ainzzorl. It falls under the category of Browsers and specifically belongs to the Add-ons & Tools subcategory.

The main purpose of Word Highlighter is to help users expand their vocabulary. With this extension, users can create a personalized list of words and phrases that they want to focus on. Once a word is added to Word Highlighter, it will be highlighted every time it appears on any webpage. This feature ensures that users are consistently exposed to the words they are trying to learn, making it easier for them to remember and understand them in different contexts.

One of the standout features of Word Highlighter is its smart matching capability. It understands variations of words and phrases, such as plurals or conjugated forms, in multiple languages including English, Spanish, French, Italian, Dutch, Norwegian, Portuguese, Russian, and Swedish. This ensures that the extension effectively highlights all relevant instances of a word, regardless of its form.

In addition to tracking and highlighting words, Word Highlighter provides various useful features. It displays a tooltip with the definition of a highlighted word when the user hovers over it, allowing for quick and easy access to the word's meaning. The extension also provides information about the number of highlighted words on each page, giving users an overview of their vocabulary exposure. Users can customize the highlight color, export and import words in csv and json formats, and even create multiple groups of words with different settings.

Privacy is a priority for Word Highlighter, as it does not send any user data anywhere. This ensures that users can use the extension without concerns about their personal information being shared. Overall, Word Highlighter is a valuable tool for language learners and anyone looking to enhance their vocabulary in a convenient and efficient manner.