Just reading a newspaper article about edible flowers which has the following flower-prep recommendation: "Remove the stamens and pistols from most flowers". Always good advice! I agree it's not that appetizing to find a gun in your salad, but really what they meant was "pistil".
Pistil is derived from a diminutive of the Latin word pilum (a pestle; one of those small club-shaped implements used to crush things in a bowl).
Above is a picture of a pestle and one of a pistil. You can see how one was named after the other.
Pistol (a handgun) is derived, unusually for English, from Czech. In Czech, the word píst'ala (a whistle, pipe, flute) was apparently first applied during the Hussite wars to a weapon with a barrel and a clear-sounding shot.
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