Ge-stun

According to the Old English Dictionary:

es;

ge-stun

n. [stunian to stun] A noise, stun, crash, whirlwind; strĕpĭtus, frăgor, turbo :-- Ðæt gestun and se storm brecaþ bráde gesceaft the stun and the storm shall break the broad creation, Exon. 22 b; Th. 61, 27; Cri. 991. Of gestune from the whirlwind, 102 a; Th. 386, 3; Rä. 4, 56. Þurh gestun per turbĭnem, Cot. 157. ge-stun