Attested:  AI iter 12 Nido

WhereNidum is generally assumed to be the Roman fort inside the modern town of Neath, at SS74749773, a little way up the river Neath from the coast.  However, to fit AI's mileages a better guess might be the marching camp at Blaen-cwm-Bach at SS79709878 more into the hills.

Name origin:  Neath probably just meant ‘low-down’, because the river and its parallel in Yorkshire, the Nidd, both pass through noticeably deep, long valleys in their upper reaches.  This simple explanation has not caught on because the excellent parallels in English (such as nether and beneath) and in other language families have no good equivalent in Celtic.  The deeper root is PIE *ni- ‘down’ itself built upon *en- ‘in’.  Alternatives, such as the ‘shining’ idea of Ekwall (1928), are unattractive.  Welsh nyth ‘nest’ from Latin nidus, plus conceivably Greek νηδυς ‘womb, belly’, derive from *nizdos ‘sit-down place’.

Notes: At least eleven more rivers across Europe were originally named *Nida, *Neida, or *Neda (Krahe 1963).

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Last edited: 27 May 2018