Unfortunately is the word you put in front of bad news to take the edge off it. "Unfortunately, the train has been cancelled." "Unfortunately, we cannot offer you the job this time."
It sits at the front of the sentence with a comma after it, or drops into the middle: the shop, unfortunately, was already shut. Emails, announcements and refusals run on it — it is the polite signal that a no is coming, and a native speaker hears the answer before the sentence finishes. Its opposites are fortunately and luckily, and its warmer spoken cousins are sadly and I'm afraid. One point of grammar: unfortunately judges the whole situation rather than the way an action was done, so it comments on the sentence, not on the verb.
1adverbunfortunatelySadly; as a matter of bad luck.
“Unfortunately, the shop had already closed by the time we got there.”
synonyms: sadly, regrettably
Unfortunately is English built at home rather than borrowed. It is unfortunate with -ly on the end, or read the other way round, un- on the front of fortunately — both routes arrive in the same place, and at the centre of it sits fortune.
From unfortunate + -ly or un- + fortunately.
Etymology from Wiktionary, CC BY-SA