the origins of the term "racism" have have been cited to be from the late 19th century to a book actually written on the subject in 1935 - so it depends on the dictionary you reference, i suppose. that said, racism is the belief that any characteristic or human trait is afford to a particular race. For example, black people are more athletic than white - that's racist. Or, Asian people are better at math -that's racist. Racism originated from Racialism - which is why some people trace its roots to before the 20th century..and place it into the late 19th century...landing square onto the lap of Leon Trotsky. But even in his context, he wasn't referring to Black and White Russians.
Racialism and Racism have their roots in the science of their day, eugenics; whose origins stem from Darwinism (in fact, the guy that "founded" eugenics was Darwin's cousin and said he was inspired by Darwin's work). This separated the notion as humans all being of the same race (which the whole world shared for thousands of years and across all faiths) and introduced the notion of evolutionary superiority - hence the KKK.
If you read the periodicals of the time, the Quakers and other Christian organizations were belittled for their "lack of scientific prowess" concerning the truth; in that they championed the human race over the ethnic race notion. This was because the science of the time was on fire with the notion of superiority -name white superiority. This was a justification for the savage acts of the industrialization of slavery and the brutality witnessed against the aborigines of Australia - where entire peoples were reduced to "livestock" because they were deemed evolutionary inferiors.
Now, we've advanced a LOT since the late 19th century. Scientific research has effectively sealed the coffin shut on the lies of Eugenics. But that doesn't mean we aren't living in it's aftermath; especially when you consider how many respond to racism with...none other than...more racism.