The authors agree in placing this surname in northern Italy, with a documented presence in Lombardy and Piedmont. They differ, however, as to its etymology.

E. Rossoni considers it clearly Lombard and proposes that it could descend from the final part of medieval names of Germanic origin, such as Valdemaro or Condulmaro. He rules out as very improbable a derivation from the Latin cognomen Maro, known for instance in the full name of the poet Virgil.

R. Brondolo offers two alternative hypotheses: that the surname is a contraction of Tamarelli, or else that it derives from the dialect term maréla, "skein of thread", which would link it with some activity related to wool. The author himself notes that this second possibility is merely conjectural.