Dictionary
Dictionary shows a word’s entry before you finish typing it. Describe a word and it finds the word: “one who makes barrels” finds cooper, and “fear of water” finds hydrophobia.
The dictionary is Webster’s Revised Unabridged of 1913. Beside each entry sit three thesauruses of the same years: Fallows for plain lists of synonyms and antonyms, Fernald for how near-synonyms differ, and Roget for the wider neighborhood of a word.
Every word on the page is a link to its own entry. A misspelling shows the nearest word, ? and * stand in for letters you don’t know, and the arrow keys step through the other matches.
The engine is Rust compiled to WebAssembly, and it runs in your browser. The word list loads first so lookup works at once, and the definitions follow. After that the app works offline, and your browser’s menu can install it to a home screen or as a desktop app.
All four books are in the public domain and come from Project Gutenberg.