Ge-unsóþian

According to the Old English Dictionary:

ge-unsóþian

p. ode; pp. od To disprove, refute, prove false; refellĕre :-- Gif se óðer ðæt geunsóþian mǽge ðæt him man onsecgan wolde if the other can disprove that which any one would charge to him, L. Edg. ii. 4; Th. i. 266, 24; L. C. S. 16; Th. i. 384, 22. ge-unsoþian