dum interim

From dum +‎ interim, both already meaning “while”.

dum interim (not comparable) (Late Latin)

1. during, while

   Synonyms: dum, interim, interea

   • [c. 400 CE, Donatus, Interpretationes Vergilianae, section 11,20:

     Interea, inquit, hoc est dum interim […]

     'Interea', he says, which means 'dum interim'[1] […]]

In several descendants, the first syllable was reinterpreted as dē- and often deleted (having been taken as optional). It may be that there existed an early *minterim, inherited as such into multiple descendant branches, but the earliest attested Romance forms appear to be those that begin with do- or de-, with the syncopated forms surfacing only later.

• Italo-Romance:
  • Italian: domentre (obsolete), ⇒ mentre
  • ⇒ Neapolitan: mente
  • ⇒ Sicilian: mentri
  • → Maltese: dment
• North Italian:
  • Old Ligurian: demente
  • Old Lombard: domente
• Gallo-Romance:
  • Catalan: dementre, ⇒ mentre, mentres
  • Franco-Provençal: domentre
  • Old French: domientres, demientres; dement, dementre, dementieres, adementiers; ⇒ mentre
    • Angevin: adementiers, ademintiers
  • Old Occitan: domentre
    • Occitan: dementre, demente
• Ibero-Romance:
  • Asturian: demientres, ⇒ mientres
  • Old Galician-Portuguese: domentres, dementres, ⇒ mentres
    • Galician: mentres
    • Portuguese: mentes
  • Old Spanish: domientre, demientre, ⇒ mientre, ⇒ mientras, mientra
    • Spanish: mientras

• Joan Coromines, José A. Pascual (1985) “mientras”, in Diccionario crítico etimológico castellano e hispánico (in Spanish), volumes IV (Me–Re), Madrid: Gredos, →ISBN, page 70
• Pianigiani, Ottorino (1907) “mentre”, in Vocabolario etimologico della lingua italiana (in Italian), Rome: Albrighi & Segati
• Walther von Wartburg (1928–2002) “dum interim”, in Französisches Etymologisches Wörterbuch (in German), volumes 3: D–F, page 178