In an agonizing manner; in a way that causes agony.(adverb)
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Use "agonizingly" in a sentence
"BARTELLA, Iraq—The plight of Iraqi Christians since the fall of Saddam Hussein has been agonizingly personal for Aram Butrus Matti."
"After agonizingly long waits, he twice got close to purchasing a pair of tickets, and both times was "booted off," once after he already had entered his credit card information, he said."
"You're getting four bars and yet broadband is agonizingly slow because too many users are trying to jam bits through at the same time."