The state, condition, or relationship of being a child; the quality or status of childhood.
Old English cild + -ship (Old English -scipe, meaning state or condition); parallel to words like friendship, kinship, and leadership which all use this suffix.
The -ship suffix was incredibly productive in English—you can add it to almost anything to mean 'the state of being' that thing, which is why we have everything from friendship to ownership to dictatorship.
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