Alternative etymologies have also been suggested by scholars. The Celtic theme nantu-, cognate with Welsh nant, ‘valley, water-course, stream’, Breton nant, ‘valley’ and Old Cornish nans, ‘vallis’, designates the ‘valley’, the ‘watercourse’, the ‘stream’, that is the place where the river flows.⁷⁰⁶ In the Alps, the ‘nant’ is a common appellation of mountain torrents. The second part of her name suelta has given rise to various etymologies. On the one hand, Delamarre and Olmsted suggest it could be related to the IE root *suel designating the ‘sun’.⁷⁰⁷ Nantosuelta’s name would therefore mean ‘Sun Valley’, that is the one who makes the valley bloom.⁷⁰⁸ Her association with the sun could be evoked by the radiant head surmounting her image on the relief* from Speyer, but this remains dubious. On the other hand, Vendryes, Schmidt and Lambert maintain that it suelta is derived from verbal theme *swel-, ‘to curve’.⁷⁰⁹ Moreover, the ending of her name in –ta, found for instance in Rosmerta or Segeta, indicates it is a name of action. Nantosuelta, broken down as *nantos-sweltâ, is generally understood as ‘Winding Brook’ or the ‘Meanders of the Stream’.⁷¹⁰

Lambert, who does not dismiss the possibility of this etymology*, nonetheless argues that the term nantu- could not have evolved in a form nanto-. He proposes to see an inflected form of a theme in –u-. Nantōs could then stand for an older *nantous, the genitive of nantu-s, ‘stream’, ‘valley’. He compares the second element of her name -wel-tâ to Welsh gwellt and Breton gueot, ‘hay’ or ‘grass to be cut’. Accordingly, her name would be a ‘juxtaposed’ noun rather than a compound noun - genitive of a possessive phrase + noun in the nominative - and would designate ‘the meadows’, ‘the pasture of the valley’.⁷¹¹ In view of those various etymologies, Nantosuelta clearly stands as a goddess originally embodying the valley, the streams, the fields and the landscape.