grevis

Blend of gravis (“heavy”) +‎ levis (“light”). Attested in a glossary^[1] written in the eighth century CE.^[2]

grevis (neuter greve); third-declension two-termination adjective (Early Medieval Latin)

1. heavy
2. difficult

• AIS: Sprach- und Sachatlas Italiens und der Südschweiz [Linguistic and Ethnographic Atlas of Italy and Southern Switzerland] – map 407: “è pesante” – on navigais-web.pd.istc.cnr.it
• Walther von Wartburg (1928–2002) “gravis”, in Französisches Etymologisches Wörterbuch, volume 4: G H I, page 265