The definition of a dagger is a short weapon with a sharp point that is used for stabbing, or something that hurts someone like a weapon.
(noun)See dagger in Webster's New World College Dictionary
noun
Origin: ME daggere < OFr dague < OProv daga
transitive verb
See dagger in American Heritage Dictionary 4
noun
Origin:
Origin: Middle English daggere
Origin: , alteration of Old French dague
Origin: , from Old Provençal dague
Origin: or Old Italian daga
Origin: , both perhaps from Vulgar Latin *dāca (ēnsis), Dacian (knife)
Origin: , from feminine of Latin Dācus
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