Likely a Scottish place name or surname (as in House of Haddo), relating to a historic location in Aberdeenshire, Scotland.
From Scottish Gaelic or Old English origins, possibly related to 'head' or a geographical feature. The name appears in Scottish historical records as a barony.
Haddo is famous in literary circles as the setting of the National Trust property Castle Fraser in Scotland, and even inspired Robert Louis Stevenson references.
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