a·ston·ish 
(ə-stŏnĭsh)
(ə-stŏnĭsh)tr.v. as·ton·ished, as·ton·ish·ing, as·ton·ish·es
To fill with sudden wonder or amazement. See Synonyms at surprise.
[Alteration of Middle English astonen, from Old French estoner, from Vulgar Latin *extonāre : Latin ex-, ex- + Latin tonāre, to thunder; see (s)tenə- in the Appendix of Indo-European roots.]
a·stonish·ing·ly adv.