to fill with sudden and overpowering surprise or wonder; amaze: Her easy humor and keen intellect astonished me.
Origin: 1525–35;Middle Englishastonyen, astonen, probably < dialectal Old French*astoner,Old Frenchestoner < Vulgar Latin*extonāre, for Latinattonāre to strike with lightning, equivalent to ex-ex-1, at-at- + tonāre to thunder; extended by -ish2, perhaps reflecting Anglo-French*astonir < dialectal Old French
[C15: from earlier astonyen (see astonied), from Old French estoner, from Vulgar Latin extonāre (unattested) to strike with thunder, from Latin tonāre to thunder]
mid-14c., astonien, from O.Fr. estoner "to stun, daze, deafen, astound," from V.L. *extonare, from L. ex- "out" + tonare "to thunder" (see thunder); so, lit. "to leave someone thunderstruck." The modern form (influenced by English verbs in -ish, e.g. distinguish, diminish)
is attested from c.1530. Related: Astonishment.
"No wonder is thogh that she were astoned" [Chaucer, "Clerk's Tale"]