The craft, trade, or workshop of a gunsmith; the practice of making and repairing firearms.
From gunsmith + -ery, a suffix indicating a place, occupation, or practice (from French -erie). This word follows the English pattern of creating abstract nouns from crafts and trades, similar to 'blacksmithery' or 'carpentry.'
The suffix '-ery' is a linguistic fossil showing how English borrowed trade terminology from French after the Norman Conquest, which is why we say 'gunsmithery' rather than 'gunsmithing' as the formal craft name.
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