A racified person is a person who people considers to be of a certain race. In western countries, white people are usually zero-category, while everyone else often gets racified. Note that this division into races is something that people do, not some kind of natural or biological fact. Who is racified and who isn't and in what ways depend on cultural context.
To racify a person or group is often to do racism against that person or group – which includes the discursive act of constructing the racified as being “a race” in the first place. Racification is why racism can be a thing while race itself isn't a thing.