Look Up

Double-click any word to see what it means, without leaving the page.

Most dictionary extensions call an API that times out on ordinary words. "ubiquitous", "gaslighting" and "kick the bucket" all fail against it. Look Up uses Wiktionary, which answers all of them, and then adds the part those extensions are missing: a ranking layer that decides which definition you actually wanted. PICKS THE RIGHT SENSE Wiktionary orders senses by lexicographic convention rather than usefulness. Ask it for "ran" and the first result is an ISO 639-3 language code. Ask for "Apple" and you get a nickname for New York City. Look Up scores every candidate on part of speech, sense labels, usage examples and document order, and drops the junk. FOLLOWS INFLECTIONS TO A REAL DEFINITION "geese" returns only "plural of goose", which is not a definition. Look Up follows the pointer, fetches "goose", and shows the actual meaning, tagged geese to goose. The same holds for "ran", "better" and "mice". READS CONTEXT FROM THE PAGE, ON YOUR MACHINE The site you are on, the page title, and the words either side of your selection all feed the ranker. "daemon" on a programming site gives you the background process; "daemon" on a mythology site gives you the minor deity. This analysis runs entirely on your own machine. Only the bare word is ever sent to Wiktionary, never the sentence, the title, or the URL. LOOKS UP PHRASES, NOT JUST WORDS A double-click can only ever catch one word. Drag across several and hold the button still for a moment and the whole phrase is looked up, as a unit first so that idioms with their own entries resolve as one thing. Right-clicking a selection works too. TRANSLATES WITHOUT A TRANSLATION SERVICE English Wiktionary stores foreign words with English glosses, so "Wasser" gives you "water" from the very same request. Your language comes from your browser settings and you are never asked for it. EXPLAINS WHOLE SENTENCES Select a passage and it picks out the terms you are likely stuck on and defines each one. Which words count as hard is decided against a bundled word list, on your machine. The passage itself is never transmitted. PAGE THROUGH THE ALTERNATIVES Ranking is a heuristic, so the runners-up stay one keystroke away. The arrow keys, or the arrows on the card, walk the rest in score order. OPTIONAL AI EXPLANATION Off by default. If you want a passage restated in plain English you can connect your own API key for OpenRouter, Anthropic, or any OpenAI-compatible endpoint. Until you do, the extension has no permission to contact any of them. PRIVACY WAS THE DESIGN CONSTRAINT No analytics. No telemetry. No lookup history, because the cache lives in memory and dies with the background page. No remote code. Content scripts never make network requests, so the page you are reading cannot observe your lookups. Open source under MPL-2.0