Look Up Words With a Three-Finger Tap on Mac

Hover the pointer over any word, tap the trackpad lightly with three fingers, and macOS floats a card with the definition, thesaurus entries, Wikipedia summary, and — depending on the word — Siri Knowledge, films, or map results. It's the fastest dictionary on the Mac, and it's one dropdown away for anyone whose trackpad ignores the gesture today.

Set Look up to a three-finger tap

1. Open System Settings → Trackpad.
2. In the Point & Click tab, find Look up & data detectors.
3. Open its menu and choose Tap with Three Fingers.

The setting has three states on macOS 13 through 15: Force Click with One Finger (the default on Force Touch trackpads), Tap with Three Fingers, and Off. Whichever you pick applies immediately; switching back is the undo.

Then test it: rest the pointer on a word in Safari or Notes and tap — a light touch, not a click — with three fingertips together. The Look Up card appears anchored to the word.

What the popover gives you

• Dictionary and thesaurus — the built-in New Oxford American definitions with synonyms, offline.
• Wikipedia — a summary card when the term matches an article.
• Siri Knowledge and media — people, places, films, and units often get rich cards.
• Translation — on recent macOS versions, a Translate section appears for foreign-language words; you can add dictionaries for other languages in the Dictionary app's settings.

The same gesture also powers data detectors: tap a street address, flight number, or date and macOS offers a map preview, flight status, or a calendar event instead of a definition.

Three-finger tap or force click?

Both routes open the identical card, so it's purely about ergonomics. The force click (press, then press deeper on one finger) keeps three-finger taps free but is easy to trigger mid-drag if you press heavily. The three-finger tap is deliberate and works on trackpads without Force Touch — but it will collide with three-finger drag if you've enabled that in Accessibility, since a tap and a drag-start look alike to the trackpad. If you use three-finger drag, stick with the force click option.

Turning it off — or aiming it better

If cards keep popping up while you type or scroll, set Look up & data detectors to Off. Lookups remain available on demand from the right-click menu (Look Up "word") and from ⌘⌃D with text selected — the keyboard shortcut works regardless of the trackpad setting, and many heavy users prefer it precisely because it never fires by accident.

A middle path: keep the gesture but retrain to tap with fingers spread slightly apart and briefly — accidental triggers almost always come from three fingers resting on the pad during a pause, and a crisper tap habit eliminates them without giving anything up.

Make the results more useful

The card's contents are configurable. Open the built-in Dictionary app, then its Settings, and tick the reference sources you want — additional languages, bilingual dictionaries like Spanish–English, or Wikipedia in another language — and drag them into priority order. Everything you enable downloads for offline use and starts appearing in the three-finger-tap card immediately. It's the difference between a gadget and a genuinely good reading tool if you work across languages.

Two quirks worth knowing: the gesture targets the word under the pointer, not the text cursor, so aim before you tap; and in PDFs the text layer must be real text — scanned pages without OCR give you nothing to look up. When a tap comes up empty in an app, try selecting the word and pressing ⌘⌃D; if that fails too, the app simply doesn't expose its text to Look Up, and no trackpad setting will change that.