Struck with amazement (6)
I believe the answer is:
aghast
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">struck with amazement</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for aghast that I've seen before include "Stupefied with horror" , "Taken aback with horror" , "Filled with horror or shock" , "Shocked, dumbfounded" , "'Horrified, shocked (6)'" .)