1998 Roosevelt Nickel - A Double Die Or Double Strike?

Guessing Machine Doubling. Here is a definition

Machine Doubling usually occurs with dies that have normal designs on them - the doubling is caused by the die bouncing and hitting the coin again, slightly off-kilter. This actually flattens part of the edges of some of the letters on the coins, effectively making them thinner than they would have been had the coin been struck normally. So, Machine Doubling is flattened down, and takes up part of the normal thickness of the letters.

Notice the flattening of left side of in god we trust and the doubling is all in one direction on the date.

Not an expert but I been looking at a lot of posts and I'm guessing this is what the pros will call it as well :)