An archaic or dialectal phrase or compound term possibly meaning a hair-like structure or object; origin and usage are uncertain.
From Old English 'hær' (hair) + 'of' (of, from Old English 'of'). This appears to be an obsolete compound where the meaning is no longer clear.
Words like 'hairof' demonstrate how English has lost countless compound terms over centuries—as language became more standardized and written communication improved, local and specialized compounds fell out of use.
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