Dictionaries are useless!!!!

[Act_of_Reparation]

12. Dictionaries are bad places to go if you are looking for very specific information

Miriam-Webster will give you a decent idea of what "racism" generally entails, but it won't give you much insight into the decades' worth of attention paid to the issue by, say, sociologists, psychologists, or political scientists. The best you're going to get from a dictionary in such situations is the definition of a word as it is used in common parlance; it is a good jumping-off point, but you're going to have to dig deeper for a more complete understanding of the term and its contextual usages.