Ge-þióstrian

According to the Old English Dictionary:

ge-þióstrian

p. ode; pp. od To obscure; obscūrāre :-- Seó sunne oferlíht ealle óðre steorran, and geþióstraþ mid hire leóhte the sun outshines all other stars, and obscures [them] with her light, Bt. titl. ix; Fox xii. 2. Sunna biþ geþióstrod sol contenebrabitur, Mk. Skt. Lind. 13, 24. ge-þiostrian