Byrðen-strang

According to the Old English Dictionary:

byrðen-strang

ad; Burthen-strong, strong to bear burdens; oneribus portandis robustus :-- Assa is stunt nýten, and byrðenstrang an ass is a foolish beast, and strong for burdens, Homl. Th. i. 208, 13. byrðen-strang