When I was learning English by watching CNN news, I saw a news with the title “ The polls show Biden is a clear favorite 100 days out from an unprecedented election”, I want to know that is “out from” a phrase here. And if it is, what’s the meaning of it.
"Out from" is another way of saying "away from." I hear people say "away from" more often than "out from," and "away from" is the more formal way of saying it. You could say "The polls show Biden is a clear favorite 100 days away from an unprecedented election." You could even say "The polls show Biden is a clear favorite 100 days from an unprecedented election." The word "out" or "away" is unnecessary in this case, but there is nothing wrong with using "away from" or "out from." In more formal writing, use "away from" instead of "out from."
Time may be referred to as if it were a physical location. For instance, we may ask where something happens in a movie, rather than when. This may come from books, where time is more obviously physical (which page you’re on).
- The election is 100 days in the future.
Means the same as:
- The election is 100 days out (or away).
The assumed reference point is now or here unless stated otherwise.
In your example, the author is counting down the days until the election, a fixed reference point in time, so this is inverted: we are now 100 days out (or away) from the election.