Míddel-ǽdr

According to the Old English Dictionary:

e;

míddel-ǽdr

f. A middle vein, median vein :-- Lǽt him blód of innanearme of þǽre miclan ǽdre þǽre middelǽdre, Lch. ii. 234, 6. Sceal mon on þǽre middelǽdre blód lǽtan, 210, 11. middel-ædr