early 14c., "burden, vex, inconvenience," from Old French encombrer "to block up, hinder, thwart," from Late Latin incombrare, from in- "in" (see in-(2)) + combrus "barricade, obstacle," probably from Latin cumulus "heap" (see cumulus). Meaning "hinder, hamper" is attested in English from late 14c. Related: Encumbered; encumbering.