Uncertain. Many theories have been proposed. Possibly a singularised plural of strug (now a regional term found in Besarabia), which may be related to strung (“lathe”), strunji or the verb struji (“to clean feathers, branches, cobs of corn, etc.; to shave or scrape off; to chisel”), a regionalism of Slavic origin (compare the semantic development of Spanish raspa (“bunch of grapes”) from the verb raspar (“scrape; file or sand down”), French grappe (“bunch, cluster”) from grapper (“pick grapes”)). Alternatively, strug may derive from a local Vulgar Latin *trugus, from Ancient Greek τρύγος (trúgos), τρυγή (trugḗ) ("vine harvest"). Other less likely etymologies include a Latin *stribulus or *strubulus, a Gepid thrubilo or struwilo, corresponding to German Träublein, or a substratum origin (although the term doesn't seem to have an Albanian or other Balkan equivalent). Replaced Old Romanian auă, from Latin uva.
strugure m (plural struguri)