Happening through bad luck, or because of some unfortunate event.(adverb)
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Use "unfortunately" in a sentence
"The term unfortunately has been hijacked by those enamored with the so called trendier parts of Eastern religions and new age movements."
"The title unfortunately evokes its predecessor, a 1978 "Star Wars" clone that presented humanity fleeing through space, pursued by robots with the same blinking red LEDs that was later adopted by the talking car in “Knight Rider.”"
"I don't even know the title unfortunately and since I can't find any mention of it anywhere on the net I fear it may have been an unauthorized bio."