Struck by shock, terror, or amazement. (adjective)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "aghast" in a sentence
"The slim night elf sat atop his cat, his expression aghast."
"What should have everyone aghast is that this man fantasizes himself as Presidential material."
"Behold him next assuming the reins of government at a time when every other mind on earth would have shrunk aghast from the fearful task, or sunk beneath its complicated perils."