macOS includes a highly integrated dictionary and web search feature called “Look Up.” By default, if you hover your mouse cursor over a word in Safari, Mail, or Pages and perform a firm three-finger tap on your trackpad (or a Force Click on newer models), a large yellow popup window appears on your screen. This window displays dictionary definitions, Wikipedia summaries, Siri suggestions, and location data related to the word you tapped.
While this is an excellent tool for students reading complex literature, it is incredibly frustrating for users who rely heavily on trackpad gestures. If you rest your fingers too heavily on the glass while scrolling through a dense webpage or coding in an IDE, macOS will frequently misinterpret your resting fingers as a three-finger tap. The dictionary popup will violently interrupt your workflow, blocking the text you were trying to read and forcing you to click away to dismiss it. To ensure you never accidentally trigger the dictionary again, you must completely disable the Look Up gesture.
Disabling the Look Up Gesture via Trackpad Settings
Apple allows you to specifically disable this individual gesture without affecting your other multi-touch trackpad settings.
- Click the Apple Logo in the extreme top-left corner of your Mac’s screen and select System Settings….
- Scroll down the left-hand navigation sidebar and click on Trackpad.
- In the main panel, ensure you are on the Point & Click tab at the top.
- Look for the setting labelled Look up & data detectors.
- Click the dropdown menu next to it (which will likely say “Tap with three fingers” or “Force Click with one finger”).
- Select the Off option from the dropdown menu.
The change takes effect immediately. Close the System Settings window and test it by opening a webpage, highlighting a word, and aggressively tapping the trackpad with three fingers. The yellow dictionary popup will no longer appear, allowing you to scroll and rest your fingers on the glass without fear of accidental interruptions.