In an astonishing manner; so as to surprise or astonish.(adverb)
Very; used as an intensifier.(adverb)
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Use "astonishingly" in a sentence
"Detroit, astonishingly, is still the 11th-largest city in the U.S."
"Mr. Domingo, still in astonishingly robust voice, dominated his scenes; Mr. Castronovo, in a more lyric tenorial vein, brought both passion and restraint to Mario, and seemed to be singing in a different opera."
"Despite the near-freezing temperature, people are dressed in astonishingly little."