The v- has been radically treated as a w- Germanic,A. Dauzat and Ch. Rostaing, Op. cit. where *Wap, then Gap (see for this type of evolution the wasp, Latin vespa, treats words as *wespa; mistletoe, Latin viscum, treated as *wiscum, etc.,However, these terms have not been of Germanic influence in the other Romance languages, including Provençal : Latin vespa > Provençal vespa, Latin viscum > Provençal vesc. depending on the phonetic path [w] > [gw] > [g]). This phonetic evolution would be more specifically made under the influence of the Gothic language.A. Farnaud, Étymologie du nom de Gap Bulletin de la Société d'études des Hautes-Alpes, année 1905, pages 431 à 434.
