barrow (n.1) Look up barrow at Dictionary.com
"vehicle for carrying a load," c.1300, barewe, probably from an unrecorded Old English *bearwe "basket, barrow," from beran "to bear, to carry" (see bear (v.)). The original had no wheel and required two persons to carry it.
barrow (n.2) Look up barrow at Dictionary.com
"mound," Old English beorg (West Saxon), berg (Anglian) "barrow, mountain, hill, mound," from Proto-Germanic *bergaz (cognates: Old Saxon, Old Frisian, Old High German berg "mountain," Old North bjarg "rock"), from PIE root *bhergh- (2) "high, elevated" (cognates: Old Church Slavonic bregu "mountain, height;" Old Irish brigh "mountain;" Welsh bera "stack, pyramid;" Sanskrit b'rhant "high," brmhati "strengthens, elevates;" Avestan brzant- "high," Old Persian bard- "be high;" Greek Pergamos, name of the citadel of Troy). Obsolete except in place-names and southwest England dialect by 1400; revived by modern archaeology.
In place-names used of small continuously curving hills, smaller than a dun, with the summit typically occupied by a single farmstead or by a village church with the village beside the hill, and also of burial mounds. [Cambridge Dictionary of English Place-Names]
Meaning "mound erected over a grave" was a specific sense in late Old English. Barrow-wight first recorded 1869 in Eirikr Magnusson and William Morris's translation of the Icelandic saga of Grettir the Strong.