The state, condition, or dignity of being gentle; the rank or status of a person of gentle birth.
From gentle plus the noun suffix -hood (meaning state or condition, from Old English had). This word combines the social rank meaning of gentle with the abstract state-of-being suffix.
The suffix '-hood' is ancient in English—we use it for childhood, adulthood, knighthood, priesthood. 'Gentlehood' is less common now because 'gentility' took over that meaning, showing how languages naturally consolidate synonyms over centuries.
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