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knife

(nīf)

n. pl. knives (nīvz)

1. A cutting instrument consisting of a sharp blade attached to a handle.

2. A cutting edge; a blade.

v. knifed, knif·ing, knifes

v.tr.

1. To use a knife on, especially to stab; wound with a knife.

2. Informal To betray or attempt to defeat by underhand means.

v.intr.

To cut or slash a way through something with or as if with a knife: The boat knifed through the waves.

Idiom:

under the knife Informal

Undergoing surgery.

[Middle English knif, from Old English cnīf, from Old Norse knīfr.]

knifer n.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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