α. late Old English–Middle English sibreden, Middle English sibberadyn, Middle English sibraden, Middle English sibradyn (in a late copy), Middle English sibredin, Middle English sybredyn, Middle English sybrydyng; Scottish pre-1700 sybredyn.
β. Middle English cybrede, Middle English sibbered, Middle English sibbrede, Middle English sibred, Middle English sybrede, Middle English sybreed, Middle English–1500s sibrede, late Middle English sybre (probably transmission error), 1500s sybberid, 1500s sybbred, 1500s sybrade, 1500s sybred; English regional (chiefly East Anglian) 1600s sibberidge, 1600s 1800s sibbered, 1600s 1800s– sibrit, 1800s sibberet, 1800s sibbit, 1800s sibbret, 1800s siberet, 1800s sibret, 1800s sibright, 1800s sybbrit, 1900s sibritt.
γ. Scottish pre-1700 sibrend, pre-1700 sibrent.