The official position or rank of being a constable; the tenure or status of holding the office of constable.
From constable + -ship (suffix denoting rank, office, or state). The -ship suffix is Germanic in origin and creates nouns describing positions of authority or conditions.
The -ship ending appears in 'kingship' and 'friendship' because it originally meant a state or condition; constableship wasn't just a job but an entire legal and social standing in medieval society.
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