A pocketknife is a folding knife that's small enough to fit in your pocket. Some fancy pocketknives have many blades and little tools that can fold back into the handle.

You can also call a pocketknife a jackknife, or in Britain, a penknife. Pocketknives' blades fold into their handles, so you can safely carry the knife in your pocket or bag. Multi-tool pocketknives, in addition to sharp blades, often have tiny screwdrivers, files, bottle openers, and other tools. Pocketknives are used for whittling, hunting, cutting twine, slicing fruit, and many other tasks.

Definitions of pocketknife
  1. noun
    a knife with a blade that folds into the handle; suitable for carrying in the pocket
    synonyms: pocket knife
    see moresee less
    clasp knife, jackknife
    a large knife with one or more folding blades
    a small pocketknife; originally used to cut quill pens
    flick knife, flick-knife, switchblade, switchblade knife
    a pocketknife with a blade that springs open at the press of a button
    type of:
    edge tool used as a cutting instrument; has a pointed blade with a sharp edge and a handle
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