When you are reading a complex document or a high-level academic article on your Mac and encounter a word you don’t recognize, your first instinct is likely to open a new tab in Safari and search Google for the definition.
This breaks your concentration and takes you away from your work. Fortunately, macOS has a powerful, built-in Dictionary application that is deeply integrated into the entire operating system, allowing you to instantly define words without ever opening a web browser.
The Fastest Way: The “Look Up” Gesture
If you are using an Apple Magic Trackpad or a MacBook with a built-in trackpad, you can define almost any word on your screen with a single gesture.
- Move your mouse cursor so it is hovering directly over the word you want to define (e.g., in Safari, Mail, or Pages).
- Firmly press down on the trackpad with one finger until you feel a “click” (Force Touch), OR gently tap the trackpad with three fingers simultaneously.
A small, elegant pop-up window will instantly appear directly above the word, displaying its dictionary definition, pronunciation guide, and even a thesaurus entry if applicable. Once you finish reading, simply click anywhere else on the screen to dismiss the pop-up.
Using the Spotlight Search
If you aren’t currently looking at the word on your screen, but simply want to look up a word you heard, you can use the Mac’s universal search bar.
- Press Command (⌘) + Spacebar to open Spotlight Search.
- Type the word you want to define (e.g., “ubiquitous”).
- Look at the search results. Near the top of the list, you will see a “Definition” section displaying the exact meaning of the word from the built-in dictionary.
Opening the Full Dictionary Application
If you want to read a longer entry, browse synonyms, or look up Wikipedia articles directly from the desktop, you can open the standalone Dictionary app.
- Open your Applications folder (or use Spotlight search).
- Locate and launch the app named Dictionary.
- Use the search bar in the top right corner to look up any word.
By default, the Dictionary app searches the New Oxford American Dictionary, the Oxford American Writer’s Thesaurus, and Apple’s own glossary. However, you can click “Dictionary” in the top menu bar, select “Settings,” and add dozens of foreign language dictionaries or specialized reference books to your Mac.